# Highlights of Quantum Information (DQI) Talks @ APS 2020 March Meeting

American Physics Society (APS) March meeting is one of the largest physics meetings in the world. In 2020, the meeting was canceled due to concerns over the rapid spread of COVID-19.

To help the community quickly catch up on the work to be presented in this meeting, Paper Digest Team processed all talk abstracts, and generated one highlight sentence (typically the main topic) for each. Readers are encouraged to read these machine generated highlights / summaries to quickly get the main idea of each talk. This article is on the talks related to **Quantum Information (DQI)**.

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#### TABLE : Quantum Information (DQI)

Title | Authors | Highlight | Session | |
---|---|---|---|---|

1 | Rydberg physics for quantum computing in arrays of neutral atom qubits | King, Jonathan; Papageorge, Alexander; Hong, Sabrina; Notermans, Remy; Lester, Brian; Kondov, Stanimir; Kotru, Krish; McDonald, Mickey; Coxe, Robin; Sivarajah, Prasahnt; Bloom, Benjamin | To this end we discuss Rydberg interactions for quantum computing with trapped single atoms, including simulations of the full Hilbert space relevant to 2-qubit gates. | Session 1: Advances in AMO Quantum Information and Technologies |

2 | Robustness and sensitivity to imperfections in the dynamics of general observables within near-term quantum simulators | Poggi, Pablo; Lysne, Nathan; Kuper, Kevin; Jessen, Poul; Deutsch, Ivan | We analyze the robustness of analog quantum simulators in the presence of weak perturbations. | Session 1: Advances in AMO Quantum Information and Technologies |

3 | Sampling complexity of interacting bosonic random walkers on a lattice | Muraleedharan, Gopikrishnan; Ray, Sayonee; Chapman, Adrian; Miyake, Akimasa; Deutsch, Ivan | In a previous work, we studied this problem in the context of simulating boson sampling by noninteracting bosonic atoms on a one-dimensional lattice [1]. | Session 1: Advances in AMO Quantum Information and Technologies |

4 | Quantum amplification of boson-mediated interactions | Burd, Shaun; Srinivas, Raghavendra; Knaack, Hannah; Ge, Wenchao; Wilson, Andrew; Wineland, David; Leibfried, Dietrich; Bollinger, John; Allcock, David; Slichter, Daniel | General methods for amplifying these interactions through parametric driving of the boson channel have been proposed for a variety of quantum platforms, but an experimental demonstration has yet to be realized. | Session 1: Advances in AMO Quantum Information and Technologies |

5 | TDDFT potential inversion applied to spin systems on noisy quantum computers | Brown, James; Yang, Jun; Whitfield, James | In this talk, we discuss the application of this method to describing interacting spin systems (which can be implemented readily on quantum computers) as a non-interacting Kohn-Sham system. | Session 1: Advances in AMO Quantum Information and Technologies |

6 | Electric field in a two-dimensional time-multiplexed photonic quantum walk | Chalabi, Hamidreza; Barik, Sabyasachi; Mittal, Sunil; MURPHY, THOMAS E.; Hafezi, Mohammad; Waks, Edo | One approach to mimic the effect of electric fields is through the use of synthetic gauge fields. | Session 1: Advances in AMO Quantum Information and Technologies |

7 | Experimental few-copy multipartite entanglement detection | Saggio, Valeria; Dimić, Aleksandra; Greganti, Chiara; Rozema, Lee; Walther, Philip; Dakic, Borivoje | Recently, a single-shot probabilistic method was proposed [1], wherein it was shown that even a single detection event can be sufficient to verify if a state exhibits entanglement. | Session 1: Advances in AMO Quantum Information and Technologies |

8 | Deterministic Logic Gates for Photonic Qubits | Heuck, Mikkel; Jacobs, Kurt; Englund, Dirk | We propose a method that converts travelling continuous-mode photons into quasi-single mode fields by absorbing them into cavities. | Session 1: Advances in AMO Quantum Information and Technologies |

9 | Accelerating quantum optics experiments using statistical learning | Cortes, Cristian; Adhikari, Sushovit; Ma, Xuedan; Gray, Stephen | In this talk, we present a new methodology for accelerating such experiments using simple statistical learning techniques such as Bayesian maximum a posteriori estimation based on few-shot data. | Session 1: Advances in AMO Quantum Information and Technologies |

10 | Machine Learning Topological Phases with a Solid-State Quantum Simulator | Lian, Wenqian; Wang, Shengtao; Lu, Sirui; Zhang, Wengang; Ouyang, Xiaolong; Wang, Xin; Huang, Xianzhi; Deng, Dong-Ling; Duan, Luming | We report an experimental demonstration of a machine learning approach to identify exotic topological phases, with a focus on the three-dimensional chiral topological insulators. | Session 1: Advances in AMO Quantum Information and Technologies |

11 | Heralding High Fidelity Entanglement Between Imperfect Artificial Atoms | Choi, Hyeongrak; Englund, Dirk | Here, we address this problem through a new single-photon entanglement protocol that uses detuned optical coupling to spin-dependent optical transitions. | Session 1: Advances in AMO Quantum Information and Technologies |

12 | A Dielectric Antenna for Quantum Emitter Interfaces | Li, Linsen; Choi, Hyeongrak; Englund, Dirk | Here, we propose a method to design a dielectric antenna for low numerical aperture optics systematically. | Session 1: Advances in AMO Quantum Information and Technologies |

13 | Sub-kilohertz optical homogeneous linewidth in transparent Er3+:Y2O3 ceramics | Fukumori, Rikuto; Huang, Yizhong; Yang, Jun; Zhang, Haitao; Zhong, Tian | Temperature, field, and time dependence studies of homogeneous linewidth reveal the limiting dephasing mechanisms as tunneling two-level systems and superhyperfine interactions between the electronic spins of erbium and nuclear spins of yttrium. | Session 1: Advances in AMO Quantum Information and Technologies |

14 | Cavity nano-optics with configurable interaction: room temperature strong coupling of single emitter | May, Molly; Fialkow, David; Wu, Tong; Park, Kyoung-Duck; Leng, Haixu; Kropp, Jaron; Gougousi, Theodosia; Lalanne, Philippe; Pelton, Matthew; Raschke, Markus | Here we establish plasmonic tip-enhanced strong coupling (TESC) with a configurable nano-tip cavity to modulate and control the cavity-emitter interaction with sub-nanometer precision, quantify coupling strength exceeding ~160 meV, at mode volumes of < 10 -6 λ 3, augmented by theoretical modeling. | Session 1: Advances in AMO Quantum Information and Technologies |

15 | A cavity enhanced spin-photon interface for NV centers in a quantum network | Weaver, Matthew; Ruf, Maximilian; Pasini, Matteo; Eschen, Martin; Hanson, Ronald | To boost emission and collection, we construct a tunable Fabry-Pérot cavity around NV centers in a diamond membrane. | Session 1: Advances in AMO Quantum Information and Technologies |

16 | Trapped Ion Quantum Computing at Honeywell | Stutz, Russell | We will report recent progress on these and other fronts. | Session 2: Advances in Atomic Systems |

17 | Sandia’s Quantum Scientific Computing Open User Testbed (QSCOUT) | Yale, Christopher; Clark, Susan; Lobser, Daniel; Pehr, Jessica; Revelle, Melissa; Maunz, Peter | Here, we present the experimental development of QSCOUT, the current and anticipated capabilities of the testbed, as well as opportunities for use of this platform. | Session 2: Advances in Atomic Systems |

18 | Building a Logical Qubit-sized Ion Trap Quantum Information Processor | Risinger, Andrew; Goldman, Michael; Egan, Laird; Noel, Crystal; Zhu, Daiwei; Biswas, Debopriyo; Cetina, Marko; Monroe, Christopher | We present the system design and architecture of a trapped ion universal quantum processor with high-fidelity quantum gates and addressing of up to 32 qubits. | Session 2: Advances in Atomic Systems |

19 | Constructing Trapped Ion Quantum Computers | Brown, Kenneth | In this talk, I will discuss our experimental work at Duke towards constructing larger ion trap quantum systems. | Session 2: Advances in Atomic Systems |

20 | A compact room temperature trapped ion system | Aikyo, Yuhi; Vrijsen, Geert; Noel, Tom; Kim, Jungsang | In this work, we present a collaborative work between Duke University and ColdQuanta, where a compact ultra-high vacuum (UHV) chamber operating at room temperature was developed for a trapped ion system. | Session 2: Advances in Atomic Systems |

21 | A trapped ion system with integrated optics for logical quantum operations | Axline, Christopher; Mehta, Karan; Matt, Roland; Oswald, Robin; Decaroli, Chiara; Stolpmann, Leon; Home, Jonathan | We present designs for operation of multiple trapping zones that could be implemented and interfaced as logical qubits. | Session 2: Advances in Atomic Systems |

22 | Individual control of an array of neutral atom qubits for quantum computing | Lester, Brian; Hong, Sabrina; King, Jonathan; Kondov, Stanimir; Kotru, Krish; McDonald, Mickey; Notermans, Remy; Papageorge, Alexander; Coxe, Robin; Sivarajah, Prasahnt; Bloom, Benjamin | Here, we present initial results on the universal single-qubit control of an array of atomic qubits comprised of neutral strontium atoms. | Session 2: Advances in Atomic Systems |

23 | Integrated optical implementation of multi-ion quantum logic | Mehta, Karan; Zhang, Chi; Malinowski, Maciej; Nguyen, Thanh-Long; Stadler, Martin; Home, Jonathan | We have designed and implemented planar traps with integrated waveguides and grating couplers, for controlling multiple 40Ca+ ions. | Session 2: Advances in Atomic Systems |

24 | Efficient Arbitrary Simultaneously Entangling Gates on a trapped-ion quantum computer | Grzesiak, Nikodem; Blumel, Reinhold; Beck, Kristin; Wright, Kenneth; Chaplin, Vandiver; Amini, Jason; Pisenti, Neal; Debnath, Shantanu; Chen, Jwo-Sy; Nam, Yunseong | In this talk, I will present an exact, linear protocol that entangles multiple arbitrary pairs of trapped-ion qubits. | Session 2: Advances in Atomic Systems |

25 | Teleported CNOT Gate in a Mixed-Species Trapped-Ion System | Erickson, Stephen; Wan, Yong; Kienzler, Daniel; Mayer, Karl; Tan, Ting Rei; Wu, Jenny; Vasconcelos, Hilma; Glancy, Scott; Knill, Emanuel; Wineland, David; Wilson, Andrew; Leibfried, Dietrich | Quantum gate teleportation achieves this, requiring only local operations within each zone, a single entangled ancilla pair split between the two zones, and classical communication. | Session 2: Advances in Atomic Systems |

26 | Laser-free trapped-ion entangling gates with an oscillating magnetic-field gradient at radio frequency | Srinivas, Raghavendra; Burd, Shaun; Sutherland, Robert; Knaack, Hannah; Leibfried, Dietrich; Wineland, David; Wilson, Andrew; Allcock, David; Slichter, Daniel | We demonstrate a recently proposed method for trapped-ion entangling gates implemented using an oscillating magnetic-field gradient at radio frequency in addition to two microwave magnetic fields symmetrically detuned about the qubit frequency [1]. | Session 2: Advances in Atomic Systems |

27 | Quantum hopping of frequency-bin entangled photon pairs | Imany, Poolad; Lingaraju, Navin; Alshaykh, Mohammed; Leaird, Daniel; Weiner, Andrew | Quantum walks of entangled particles have promising applications in simulating many-body physics, as well as in implementing quantum search algorithms. | Session 2: Advances in Atomic Systems |

28 | Improved Light-Matter Interaction in a Thulium Cavity Memory for Quantum Light Storage | Davidson, Jacob; Lefebvre, Pascal; Zhang, Jun; Oblak, Daniel; Tittel, Wolfgang | We design and implement an atomic frequency comb quantum memory using a thulium-doped crystal in an impedance matched optical cavity to create absorption of more than 90% of input signal, resulting in a memory efficiency of 27%. | Session 2: Advances in Atomic Systems |

29 | Simultaneous Measurement of 53 Superconducting Transmons on the Sycamore Processor | Chen, Zijun; Naaman, Ofer; Sank, Daniel; Klimov, Paul; Quintana, Chris; Kelly, Julian; Megrant, Anthony; Neven, Hartmut; Martinis, John | In this talk, I will discuss how we overcame some of these challenges to achieve simultaneous readout of 53 qubits on Google’s Sycamore processor, enabling the demonstration of quantum supremacy. | Session 3: Advances in Qubit Measurement |

30 | Single-shot readout and state preparation of a fluxonium qubit without the use of a parametric amplifier | Gusenkova, Daria; Spiecker, Martin; Gebauer, Richard; Gruenhaupt, Lukas; Winkel, Patrick; Valenti, Francesco; Takmakov, Ivan; Rieger, Dennis; Ustinov, Alexey; Wernsdorfer, Wolfgang; Sander, Oliver; Pop, Ioan-Mihai | Using a fluxonium qubit with a granular aluminum superinductance [4], we demonstrate single shot qubit measurements without a parametric amplifier, at a readout power corresponding to hundreds of circulating photons. | Session 3: Advances in Qubit Measurement |

31 | Measurement of quantum jumps of a fluxonium qubit using a Dimer Josephson Junction Array Amplifier operated at high power | Takmakov, Ivan; Winkel, Patrick; Foroughi, Farshad; Spiecker, Martin; Gruenhaupt, Lukas; Gusenkova, Daria; Planat, Luca; Rieger, Dennis; Ustinov, Alexey; Wernsdorfer, Wolfgang; Pop, Ioan-Mihai; Roch, Nicolas | We present quantum jump measurements acquired using up-to 100 circulating photons in the readout resonator, which allowed qubit state discrimination in tens of nanoseconds. | Session 3: Advances in Qubit Measurement |

32 | Towards autonomous digital feedback on a superconducting qubit | Zhao, Ziyi; Rosenthal, Eric; Malnou, Maxime; Schneider, Christian; Vale, Leila; Hilton, Gene; Kirchmair, Gerhard; Gao, Jiansong; Lehnert, K. | Here we present preliminary data on the state preparation and stabilization of a superconducting qubit where we keep the measurement information at the base temperature stage of the cryostat, and then use it to conditionally π pulse a qubit. | Session 3: Advances in Qubit Measurement |

33 | Isolating a qubit from amplifier backaction by coordinated switching | Rosenthal, Eric; Schneider, Christian; Malnou, Maxime; Zhao, Ziyi; Leditzky, Felix; Chapman, Benjamin; Ma, Xizheng; Palken, Daniel; Vale, Leila; Hilton, Gene; Kirchmair, Gerhard; Gao, Jiansong; Smith, Graeme; Lehnert, K. | We demonstrate a cQED qubit measurement scheme in which the qubit is isolated from amplifier backaction without ferrite circulators. | Session 3: Advances in Qubit Measurement |

34 | On-chip single-pump interferometric Josephson Isolator | Abdo, Baleegh; Jinka, Oblesh; Bronn, Nicholas; Olivadese, Salvatore; Brink, Markus; Chow, Jerry | In this work, we realize and measure an on-chip Josephson isolator, which is formed by coupling two nondegenerate Josephson mixers in an interferometric scheme. | Session 3: Advances in Qubit Measurement |

35 | Novel Measurements for Annealing Capable Flux Qubits | DeGottardi, Wade; Clarke, David; Novikov, Sergey; Basham, James; Grover, Jeffrey; Disseler, Steven; Ferguson, David | This talk discusses alternative QFP readout procedures including: (i) at early times in the anneal, (ii) for other non z-loop currents, and (iii) for Josephson phase slip qubits (JPSQs). | Session 3: Advances in Qubit Measurement |

36 | Realizing large, tunable dispersive shifts with parametric couplings | Xiao, Zhihao; Ranzani, Leonardo; Govia, Luke; Simmonds, Raymond; Aumentado, Jose; Kamal, Archana | In this work, we analyze the primary building block of such a platform — a single qubit parametrically coupled to a single-mode resonator. | Session 3: Advances in Qubit Measurement |

37 | Remote entanglement via two mode squeezed light | Cao, Xi; Liu, Gangqiang; Chien, Tzu-Chiao; Zhou, Chao; Lu, Pinlei; Hatridge, Michael | Here we present a two qubit, TMSL interferometric entangling readout. | Session 3: Advances in Qubit Measurement |

38 | Fast high fidelity quantum non-demolition superconducting qubit readout | Dassonneville, Rémy; Ramos, Thomas; Milchakov, Vladimir; Planat, Luca; Dumur, Etienne; Foroughi, Farshad; Puertas, Javier; Leger, Sebastien; Bharadwaj, Karthik Srikanth; Delaforce, Jovian; Naud, Cécile; Guichard, Wiebke; Garcia-Ripoll, Juan Jose; Roch, Nicolas; Buisson, Olivier | To overcome this, we propose and experimentally demonstrate a new readout scheme based on a transmon molecule inserted inside a 3D-cavity _[1,2]. | Session 3: Advances in Qubit Measurement |

39 | Frequency-domain pulse engineering for fast qubit readout and resonator reset | Borgani, Riccardo; Tholen, Mats; Jolin, Shan; Forchheimer, Daniel; Haviland, David | Here we present a microwave pulse scheme which, regardless of the state of the qubit, populates the readout resonator, measures the state of the qubit, and empties the resonator, all in a time much faster than 1/κ. | Session 3: Advances in Qubit Measurement |

40 | High efficiency measurement of a superconducting qubit using a directional, phase-sensitive, parametric amplifier | Lecocq, Florent; Ranzani, Leonardo; Peterson, Gabriel; Kotler, Shlomi; Cicak, Katarina; Jin, X. Y.; Simmonds, Raymond; Teufel, John; Aumentado, Jose | In this talk we will discuss how one can approach ideal measurement efficiency by directly connecting a 3D transmon to a non-reciprocal phase-sensitive amplifier [1]. | Session 3: Advances in Qubit Measurement |

41 | High fidelity dispersive qubit readout in circuit QED without using a Josephson Parametric Amplifier | Kundu, Suman; Salunkhe, Kishor; Bhattacharjee, Anirban; Hazra, Sumeru; Patankar, Meghan; Vijay, R | Here, we present and demonstrate an alternate design where qubit-cavity coupling does not rely on the dispersive approximation of the Jaynes-Cummings Hamiltonian. | Session 3: Advances in Qubit Measurement |

42 | Asymmetric Sensing Dot for Scaleable Baseband Readout of Spin Qubits | Kammerloher, Eugen; Künne, Matthias; Seidler, Inga; Ludwig, Arne; Wieck, Andreas; Schreiber, Lars; Bluhm, Hendrik | We present experimental results in GaAs of an asymmetric sensing dot (ASD), improving the sensor response by a factor of 15 compared to conventional charge sensing dots. | Session 3: Advances in Qubit Measurement |

43 | A Reservoir Computing Approach to Quantum State Measurement | Angelatos, Gerasimos; Tureci, Hakan; Khan, Saeed | In this work, we propose a hardware-based reservoir computing system for quantum state measurement and discuss its performance when compared to conventional approaches. | Session 3: Advances in Qubit Measurement |

44 | Neural Network assisted Superconducting Qubit Readout | Lienhard, Benjamin; Vepsalainen, Antti; Govia, Luke; Qiu, Yanjie; Ristè, Diego; Ware, Matthew; Kim, David; Winik, Roni; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Ribeill, Guilhem; Ohki, Thomas; Krovi, Hari; Orlando, Terry; Gustavsson, Simon; Oliver, William | Here, we present a new approach to the readout problem based on neural networks. | Session 3: Advances in Qubit Measurement |

45 | Single-Qubit Optimal Quantum Readout via Neural Networks | Tang, Wei; Leng, Zhaoqi; Houck, Andrew; Martonosi, Margaret | We explore the benefits of employing alternative classification schemes based on neural networks to improve fidelity. | Session 3: Advances in Qubit Measurement |

46 | Dispersive readout for Majorana qubits | Smith, Thomas; Bartlett, Stephen; Grimsmo, Arne | We model the interaction with each qubit and a readout resonator, and calculate the size of the qubit state-dependent dispersive shift of the resonator. | Session 3: Advances in Qubit Measurement |

47 | Tracking non-Markovian quantum dynamics of a superconducting qubit with a recurrent neural network filter | Stevenson, Noah; Koolstra, Gerwin; Mitchell, Bradley; Hashim, Akel; Barzili, Shiva; Dressel, Justin; Siddiqi, Irfan | We use quantum state tracking with continuous weak measurement to experimentally investigate non-Markovianity in a transmon superconducting qubit coupled to a readout resonator. | Session 3: Advances in Qubit Measurement |

48 | High-fidelity quantum state estimation via autoencoder tomography | Lotfallahzadeh Barzili, Shiva; Stevenson, Noah; Mitchell, Bradley; Mohseninia, Razieh; Siddiqi, Irfan; Dressel, Justin | We investigate the use of supervised machine learning, in the form of a denoising autoencoder, to simultaneously remove experimental noise while encoding one- and two-qubit quantum state estimates into a minimum number of nodes within the latent layer of a neural network. | Session 3: Advances in Qubit Measurement |

49 | Characterization and tomography of a hidden qubit | Pechal, Marek; Ganzhorn, Marc; Werninghaus, Max; Egger, Daniel; Salis, Gian; Filipp, Stefan | In our experiment we use transmon-type superconducting qubits along with parametric tunable-coupler gates to realize both types of two-qubit interactions. | Session 3: Advances in Qubit Measurement |

50 | Quantum Rifling: Protecting a Qubit from Measurement Back-action | Szombati, Daniel; Gomez Frieiro, Alejandro; Mueller, Clemens; Jones, Tyler; Jerger, Markus; Fedorov, Arkady | We show this picture breaks down when the qubit is strongly driven during measurement. | Session 3: Advances in Qubit Measurement |

51 | Rapid gate-based read-out of spins in silicon using an on-chip resonator | zheng, guoji; Samkharadze, Nodar; Harvey-Collard, Patrick; Dijkema, Jurgen; Noordam, Marc; Kalhor, Nima; Brousse, Delphine; Sammak, Amir; Scappucci, Giordano; Vandersypen, Lieven | In this talk, I will describe the use of an on-chip superconducting microwave resonator to improve the sensitivity, aided by its high quality factor and impedance. | Session 3: Advances in Qubit Measurement |

52 | Improving Multilevel Qudit Readout Fidelity During Relaxation Events via Hidden Markov Models | Martinez, Luis; Rosen, Yaniv; DuBois, Jonathan | To overcome this constraint, we demonstrate high-fidelity multi-state readout by detecting qubit relaxation with Hidden Markov Models on LLNL’s Quantum Design and Integration Testbed (QuDIT). | Session 3: Advances in Qubit Measurement |

53 | Continuous Indirect detection of stabilizers for quantum error correction | Chen, Yi-Hsiang; Brun, Todd | We provide an alternative method to passively detect the value of an operator. | Session 3: Advances in Qubit Measurement |

54 | Diagnosing Errors in Quantum Gates Using Continuous Measurements | Steinmetz, John; Jordan, Andrew | We use continuous weak measurements to track a quantum gate operation as it develops in time, which allows us to identify the full time-dependent dynamics of any systematic errors. | Session 3: Advances in Qubit Measurement |

55 | Finding Navier-Stokes fluid flows through quantum computung | Gaitan, Frank | We present a quantum algorithm that solves an arbitrary set of coupled non-linear partial differential equations and show how it can be used to solve the governing equations for a Navier-Stokes fluid. | Session 4: Algorithms and Architecture for Quantum Information |

56 | Quantum eigenvalue estimation via time series analysis | Somma, Rolando | We present an efficient method for estimating the eigenvalues of a Hamiltonian H from the expectation values of the evolution operator for various times. | Session 4: Algorithms and Architecture for Quantum Information |

57 | A robust algorithm for finding phase factors in quantum signal processing | Dong, Yulong; Lin, Lin; Meng, Xiang; Whaley, Birgitta | We present an efficient method to find the phase factors for a general real function, and demonstrate the performance for solving linear systems and eigenvalue problems. | Session 4: Algorithms and Architecture for Quantum Information |

58 | Finding symmetry-broken ground states with variational quantum algorithms | Vogt, Nicolas; Zanker, Sebastian; Reiner, Jan-Michael; Eckl, Thomas; Marusczyk, Anika; Marthaler, Michael | We use a hardware model based on the gates available in currently available quantum computers. | Session 4: Algorithms and Architecture for Quantum Information |

59 | Strategies for digital quantum simulation of bosons | Sawaya, Nicolas; Menke, Tim; Kyaw, Thi Ha; Johri, Sonika; Aspuru-Guzik, Alan; Guerreschi, Gian Giacomo | We present a general methodology for encoding truncated bosons into arrays of qubits, and consider several encoding types. | Session 4: Algorithms and Architecture for Quantum Information |

60 | A Method of Determining Excited-States for Quantum Computation | Jouzdani, Pejman; Bringuier, Stefan; kostuk, Mark | In this contribution, we propose a phenomenological approach to the calculation of low-lying excited-states of a given problem Hamiltonian. | Session 4: Algorithms and Architecture for Quantum Information |

61 | Quantum simulation by qubitization without Toffoli gates | Steudtner, Mark; Wehner, Stephanie | Building on that principle, we develop an entirely new decomposition of the entire algorithm: without Toffoli gates, we can encode the Hamiltonian into qubits within logarithmic depth. | Session 4: Algorithms and Architecture for Quantum Information |

62 | Emulation of fractional quantum Hall states with existing quantum hardware | Rahmani, Armin; Ghaemi, Pouyan; Jiang, Zhang; Roushan, Pedram; Sung, Kevin | Here we present quantum circuits to generate both the ground and quasiparticle states corresponding to the Laughlin’s $\nu=1/3$ fractional quantum Hall state in the second-quantized representation. | Session 4: Algorithms and Architecture for Quantum Information |

63 | Computing partition functions in the one clean qubit model | Narayan Chowdhury, Anirban; Somma, Rolando; Subasi, Yigit | In this talk we will present a method to approximate partition functions of quantum systems using mixed-state quantum computation. | Session 4: Algorithms and Architecture for Quantum Information |

64 | Reaction dynamics on a quantum computer | Tranter, Andrew; Love, Peter | In this talk, we present theoretical results characterising the quantum resources required for the simulation of reactions involving small numbers of light atoms through semi-classical trajectory simulation. | Session 4: Algorithms and Architecture for Quantum Information |

65 | A size-extensive scheme for variational quantum ansatzes without Trotter approximation | Herasymenko, Yaroslav; O’Brien, Thomas | In this work, we resolve this conflict by developing a framework for physically motivated ansatzes, which is fundamentally digital and thereby involves no Trotter errors. | Session 4: Algorithms and Architecture for Quantum Information |

66 | Finding the ground state of the Hubbard model by variational methods on a quantum computer with gate errors | Reiner, Jan-Michael; Wilhelm, Frank; Schön, Gerd; Marthaler, Michael | Here we study explicitly the effect of gate errors on its performance. | Session 4: Algorithms and Architecture for Quantum Information |

67 | Quantum algorithm for spectral projection by measuring an ancilla iteratively | Wei, Tzu-Chieh; Chen, Yanzhu | We propose a quantum algorithm for projecting a quantum system to eigenstates of any Hermitian operator, provided one can access the associated control-unitary evolution for the ancilla and the system. | Session 4: Algorithms and Architecture for Quantum Information |

68 | Quantum Simulation of Quantum Z2 Gauge Theory demonstrated in a GPU Simulator | Shi, Yu | We outline a quantum simulation scheme of quantum Z2 gauge theory using quantum adiabatic algorithm implemented in terms of quantum circuit, and then demonstrate it in the classical simulator QuEST using a CUDA enabled GPU server. | Session 4: Algorithms and Architecture for Quantum Information |

69 | Term Grouping Techniques for VQE and Quantum Dynamics Circuits | Gui, Kaiwen; Gokhale, Pranav; Tomesh, Teague; Ding, Yongshan; Angiuli, Olivia; Suchara, Martin; Martonosi, Margaret; Chong, Fred | We demonstrate various grouping techniques that optimize the order of these tensor products, with the goal of optimizing the total quantum resource cost. | Session 4: Algorithms and Architecture for Quantum Information |

70 | Randomized benchmarking for qudit Clifford gates | Sanders, Barry; Jafarzadeh, Mahnaz; Wu, Yadong | We introduce unitary-gate randomized benchmarking (URB) for qudit gates by extending single- and multi-qubit URB to single- and multi-qudit gates. | Session 4: Algorithms and Architecture for Quantum Information |

71 | Quantum-Computing Architecture based on Large-Scale Multi-Dimensional Continuous-Variable Cluster States in a Scalable Photonic Platform | Wu, Bo-Han; Alexander, Rafael; Zhang, Zheshen | Here, we bridge two fields—Kerr microcombs and continuous-variable (CV) quantum information—to formulate a one-way quantum computing architecture based on programmable large-scale CV cluster states. | Session 4: Algorithms and Architecture for Quantum Information |

72 | Proposed Universal Deutsch Gate Circuitry Using GaAs/InAs Quantum Dots | Bailey, Paul; Van Huele, Jean-Francois | We propose to combine two GaAs/InAs quantum dots with photon polarization in a larger circuit comprised of linear optical elements to create a spin-spin-photon polarization three qubit Deutsch Gate similar to a proposal for a CNOT gate [Bouwmeester et al., Phys. | Session 4: Algorithms and Architecture for Quantum Information |

73 | Quantum-classical transition in analog quantum supremacy subject to Markovian decoherence | Mohseninia, Razieh; Marvian, Milad; Lidar, Daniel | We study the robustness of quantum supremacy in an analog Hamiltonian version of such circuits in the presence of a Markovian environment whose noise operators commute with the system Hamiltonian. | Session 4: Algorithms and Architecture for Quantum Information |

74 | Optimal recognition of exact free-fermion solutions for spin models | Chapman, Adrian; Flammia, Steven | We connect the general problem of recognizing models which can be exactly solved in this way to the graph-theoretic problem of recognizing line graphs, which has been solved optimally. | Session 4: Algorithms and Architecture for Quantum Information |

75 | Quantum Algorithms for Approximate Dynamic Programming | Ronagh, Pooya | We present a quantum algorithm for finding approximate solutions to dynamic programming problems using the multiplicative weight update method. | Session 4: Algorithms and Architecture for Quantum Information |

76 | A Novel Tensor Network Algorithm for Simulating Large Quantum Circuits | Reyes, Justin; Zhang, Lei; Kourtis, Stefanos; Chamon, Claudio; Ruckenstein, Andrei; Mucciolo, Eduardo | To overcome this limitation, we employ a novel tensor network methodology to compute expectation values that resembles the Keldysh formalism. | Session 4: Algorithms and Architecture for Quantum Information |

77 | Gate(s)-wise Optimization for Variational Quantum Eigensolvers | Slattery, Lucas; Villalonga, Benjamin; Clark, Bryan | These states include ground states of chemistry and condensed matter models, as well as the solution to other optimization problems. | Session 4: Algorithms and Architecture for Quantum Information |

78 | The resilience of quantum random access memory to generic noise | Hann, Connor; Lee, Gideon; Girvin, Steven; Jiang, Liang | We prove that, quite surprisingly, the favorable scaling holds for general noise models (including depolarization) and hence should be achievable in realistically noisy devices. | Session 4: Algorithms and Architecture for Quantum Information |

79 | QuSP: The Quantum Simulator Package | Jones, Matthew; Carr, Lincoln | With the guidance of the Science Gateways Community Institute, and backed by OpenMPS, a highly generalizable matrix product state simulation toolkit, we will address the aforementioned gap with QuSP, the Quantum Simulator Package. | Session 4: Algorithms and Architecture for Quantum Information |

80 | Cost of Classical Strong Simulation of the T-Gate Magic State | Kocia, Lucas; Sarovar, Mohan | We examine this problem from the perspective of the cost of strong classical simulation of discrete Wigner functions in systems with odd dimension and compare with the known results for qubits. | Session 4: Algorithms and Architecture for Quantum Information |

81 | Alibaba Cloud Quantum Development Platform: Large-Scale Classical Simulation of Quantum Circuits | Zhang, Fang; Huang, Cupjin; Newman, Michael; Cai, Junjie; Yu, Huanjun; Tian, Zhengxiong; Yuan, Bo; Xu, Haihong; Wu, Junyin; Gao, Xun; Chen, Jianxin; Szegedy, Mario; Shi, Yaoyun | In this note, we report the computational experiments demonstrating the classical simulation capability of AC-QDP. | Session 4: Algorithms and Architecture for Quantum Information |

82 | Alibaba Cloud Quantum Development Platform: Applications to Quantum Algorithm Design | Huang, Cupjin; Szegedy, Mario; Zhang, Fang; Chen, Jianxin; Gao, Xun; Shi, Yaoyun | In this follow-up article, we demonstrate with figures how AC-QDP helps in testing large-scale quantum algorithms (currently within the QAOA framework). | Session 4: Algorithms and Architecture for Quantum Information |

83 | Quantum linear system solver based on time-optimal adiabatic quantum computing and quantum approximate optimization algorithm | An, Dong; Lin, Lin | We demonstrate that with an optimally tuned scheduling function, adiabatic quantum computing (AQC) can solve a quantum linear system problem with O(κ/ε) runtime, where κ is the condition number, and ε is the target accuracy. | Session 4: Algorithms and Architecture for Quantum Information |

84 | Quantum optimal algorithm for general polynomials | Li, Keren; Gao, Pan | Gradient descent algorithms, which is a first-order iterative algorithm, is widely used for optimization problems. | Session 4: Algorithms and Architecture for Quantum Information |

85 | Protecting a bosonic qubit with autonomous quantum error correction I – Theory | Wang, Chen; Gertler, Jeffrey | Here we present an autonomous error correction scheme for a bosonic qubit in a superconducting cavity, which directly corrects the dominant error channel of the system: single photon loss. | Session 5: Autonomous QEC and Bosonic Codes |

86 | Protecting a bosonic qubit with autonomous quantum error correction II – Experiment | Gertler, Jeffrey; Baker, Brian; Li, Juliang; Koch, Jens; Wang, Chen | Here we present an autonomous error correction scheme for a bosonic qubit in a superconducting cavity, which directly corrects the dominant error channel of the system: single photon loss. | Session 5: Autonomous QEC and Bosonic Codes |

87 | All-Gaussian universality and fault tolerance with the Gottesman-Kitaev-Preskill code | Baragiola, Ben; Pantaleoni, Giacomo; Alexander, Rafael; Karanjai, Angela; Menicucci, Nicolas | We show that applying GKP error correction to Gaussian input states, such as vacuum, produces distillable magic states, achieving universality without additional non-Gaussian elements. | Session 5: Autonomous QEC and Bosonic Codes |

88 | Stabilization of finite-energy Gottesman-Kitaev-Preskill bosonic codes | Royer, Baptiste; Singh, Shraddha; Girvin, Steven | In this talk, we investigate improved stabilization strategies tailored specifically for finite-energy GKP codes and study how these protocols perform in a superconducting implementation with realistic parameters. | Session 5: Autonomous QEC and Bosonic Codes |

89 | Path-independent gates for error-corrected quantum computing: Theory | Ma, Wen-Long; Reinhold, Philip; Rosenblum, Serge; Schoelkopf, Robert; Jiang, Liang | Here, we propose a general class of quantum gates on the logical system that is path independent (PI) of Markovian ancilla error trajectories, including both ancilla relaxation and dephasing errors. | Session 5: Autonomous QEC and Bosonic Codes |

90 | Path-Independent Gates for Error-Corrected Quantum Computing: Experiment | Rosenblum, Serge; Reinhold, Philip; Ma, Wen-Long; Frunzio, Luigi; Jiang, Liang; Schoelkopf, Robert | Here, we present an error-corrected construction for a logical gate set [1] enacted by a multilevel transmon ancilla on a cavity-encoded logical qubit. | Session 5: Autonomous QEC and Bosonic Codes |

91 | Error-transparent operations on a logical qubit protected by quantum error correction | Ma, Yuwei; Xu, Yuan; Mu, Xianghao; Cai, Weizhou; Hu, Ling; Wang, Weiting; Pan, Xiaoxuan; Wang, Haiyan; Song, Yipu; Zou, Changling; Sun, Luyan | Here, we demonstrate phase gate operations on a logical qubit encoded in a bosonic oscillator in an error-transparent (ET) manner. | Session 5: Autonomous QEC and Bosonic Codes |

92 | High-impedance circuits for parity measurements of cat qubits | Smith, Clarke; Villiers, Marius; Lescanne, Raphaël; Marquet, Antoine; Berdou, Camille; Kontos, Takis; Mirrahimi, Mazyar; Leghtas, Zaki | We present the design of a superconducting circuit that effectively realizes the parity-type Hamiltonian, as well as the status of its experimental implementation. | Session 5: Autonomous QEC and Bosonic Codes |

93 | Experimental implementation of fault-tolerant error syndrome measurement for pair-cat code (1/2) | Koottandavida, Akshay; Tsioutsios, Ioannis; Mundhada, Shantanu; Frunzio, Luigi; Devoret, Michel | In this talk, we will present an experimental implementation of cavities and superconducting devices that is compatible with such encoding. | Session 5: Autonomous QEC and Bosonic Codes |

94 | Experimental implementation of fault-tolerant error syndrome measurement for pair-cat code (2/2) | Tsioutsios, Ioannis; Koottandavida, Akshay; Mundhada, Shantanu; Frunzio, Luigi; Devoret, Michel | In this talk, we will present an experimental implementation of cavities and superconducting devices that is compatible with such encoding. | Session 5: Autonomous QEC and Bosonic Codes |

95 | Progress on fault-tolerant quantum computing with concatenated bosonic-qubit codes | Grimsmo, Arne; Tanuarta, Stefanus; Soule, Juliette; Baragiola, Ben; Combes, Joshua | In this talk I will discuss ongoing work to quantify the performance of bosonic error correcting codes concatenated with conventional qubit codes. | Session 5: Autonomous QEC and Bosonic Codes |

96 | Fault-Tolerant Bosonic Quantum Error Correction with the Surface-GKP Code | Noh, Kyungjoo; Chamberland, Christopher | Here, we consider the concatenation of the bosonic Gottesman-Kitaev-Preskill (GKP) code with the surface code, namely, the surface-GKP code. | Session 5: Autonomous QEC and Bosonic Codes |

97 | Majorana dimer models of holographic quantum error correction | Jahn, Alexander; Gluza, Marek; Pastawski, Fernando; Eisert, Jens | In this talk, we introduce a versatile framework of Majorana dimers capturing the intersection of stabilizer and Gaussian Majorana states. | Session 5: Autonomous QEC and Bosonic Codes |

98 | Algorithm-specific Performance Analysis of Transmon Qubit Devices | O’Keeffe, Michael; Kjaergaard, Morten; Schwartz, Mollie; Samach, Gabriel; Greene, Amy; McNally, Chris; Rosenberg, Danna; Oliver, William; Kerman, Andrew; Obenland, Kevin | Many demonstrations of quantum algorithms exhibit a tradeoff between the accuracy of the algorithm and the fidelity of the circuit that implements that algorithm. | Session 6: Characterizing Quantum Computing Systems and Components |

99 | Oscillator noise spectroscopy via displaced Schrödinger-cat states | Milne, Alistair; Edmunds, Claire; Hempel, Cornelius; Ball, Harrison; Hush, Michael; Carvalho, André; Biercuk, Michael | We present a technique for the characterization of noise in oscillator-mediated entangling operations applicable to a range of gate implementations in both trapped ion and superconducting circuit architectures. | Session 6: Characterizing Quantum Computing Systems and Components |

100 | Detector Tomography on IBM Quantum Computers and Mitigation of Imperfect Measurement | Chen, Yanzhu; Farahzad, Maziar; Yoo, Shinjae; Wei, Tzu-Chieh | We use quantum detector tomography to characterize the qubit readout in terms of measurement POVMs on IBM Quantum Computers IBM Q 5 Tenerife and IBM Q 5 Yorktown. | Session 6: Characterizing Quantum Computing Systems and Components |

101 | Characterizing mid-circuit measurements with a new form of gate set tomography part 1: Theory | Rudinger, Kenneth; Proctor, Timothy; Nielsen, Erik; Ribeill, Guilhem; Ware, Matthew; Govia, Luke; Ohki, Thomas; Young, Kevin; Blume-Kohout, Robin | We will describe this extension and demonstrate its success in simulations. | Session 6: Characterizing Quantum Computing Systems and Components |

102 | Characterizing mid-circuit measurements with a new form of gate set tomography part 2: Experiment | Ribeill, Guilhem; Ware, Matthew; Govia, Luke; Rudinger, Kenneth; Proctor, Timothy; Ohki, Thomas | To that end, we demonstrate the use of an extension to gate set tomography (GST), a highly accurate protocol for diagnosing quantum processes, to characterize intermediate measurements on a superconducting transmon qubit. | Session 6: Characterizing Quantum Computing Systems and Components |

103 | A proposed gold standard family of protocols for benchmarking and diagnosing elementary quantum gate operations | Boone, Kristine; Carignan-Dugas, Arnaud; Wallman, Joel; Hincks, Ian; Dahlen, Dar; Emerson, Joseph | We propose a family of randomized benchmarking protocols as a gold standard for assessing and diagnosing error rates on elemntary one and two qubit gates. | Session 6: Characterizing Quantum Computing Systems and Components |

104 | Efficient learning of quantum noise | Harper, Robin; Flammia, Steven; Wallman, Joel | Here I will discuss a newly introduced protocol that completely and efficiently characterizes the qubit error rates of quantum noise. | Session 6: Characterizing Quantum Computing Systems and Components |

105 | Long-Sequence Quantum Process Tomography | Sugiyama, Takanori | Here, we propose a new tomographic method with an error amplification, named long-sequence quantum process tomography. | Session 6: Characterizing Quantum Computing Systems and Components |

106 | Spectral Quantum Tomography | Helsen, Jonas; Battistel, Francesco; Terhal, Barbara | We introduce spectral quantum tomography, a simple method to extract the eigenvalues of a noisyfew-qubit gate, represented by a trace-preserving superoperator, in a SPAM-resistant fashion, usinglow resources in terms of gate sequence length. | Session 6: Characterizing Quantum Computing Systems and Components |

107 | Independent State and Measurement Characterization on Quantum Computers | Lin, Junan; Wallman, Joel; Laflamme, Raymond | In this work, we approach this problem by assuming certain structure on SPAM and gate elements, and derive a simple experimental procedure to separately estimate the SPAM error strengths on a QPU. | Session 6: Characterizing Quantum Computing Systems and Components |

108 | Extracting Coherence Information From Random Circuits Using “Speckle Purity Benchmarking” | Kelly, Julian; Boixo, Sergio; Chen, Zijun; Martinis, John; Neven, Hartmut | Here, we introduce a method that allows us to extract the same information with exponentially fewer sequences from raw XEB data. | Session 6: Characterizing Quantum Computing Systems and Components |

109 | Quantum noise spectroscopy for multiaxis noise models | Norris, Leigh; Paz Silva, Gerardo; Beaudoin, Felix; Viola, Lorenza | To move beyond dephasing-dominated platforms, we extend frequency-comb based QNS to a multi-axis qubit noise model that takes into account both T 1 and T 2 processes from either classical or quantum environments. | Session 6: Characterizing Quantum Computing Systems and Components |

110 | Cayley path and quantum computational supremacy: A proof of average-case #P-hardness of Random Circuit Sampling with quantified robustness | Movassagh, Ramis | A one-parameter unitary-valued interpolation between any two unitary matrices is constructed based on the Cayley transformation, which extends our work. | Session 6: Characterizing Quantum Computing Systems and Components |

111 | Credibility of noisy intermediate-scale quantum computers | Datta, Animesh; Ferracin, Samuele; Kapourniotis, Theodoros; Jackson, Andrew | I will present methods that can provide, for a given problem, an upper bound on the variation distance between an experimentally obtained output from a noisy quantum computer and the ideal output from a noiseless device. | Session 6: Characterizing Quantum Computing Systems and Components |

112 | Logical Cooling for Noise Reduction in Analogue Quantum Simulation | Clark, Susan; Hogle, Craig; Stephens, Jaimie; Young, Kevin; Blume-Kohout, Robin; Stick, Daniel; Maunz, Peter | Here, we report our progress using a technique to remove errors in the computational basis of the system, without resorting to a full error correcting scheme, to both measure and increase an analogue quantum simulator’s robustness to noise. | Session 6: Characterizing Quantum Computing Systems and Components |

113 | Characterizing the Propagation of Gate Errors in Experimental Quantum Algorithms | Samach, Gabriel; Kjaergaard, Morten; Greene, Amy; Schwartz, Mollie; Bengtsson, Andreas; O’Keeffe, Michael; McNally, Chris; Sung, Youngkyu; Krantz, Philip; Braumueller, Jochen; Winik, Roni; Kim, David; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Rosenberg, Danna; Obenland, Kevin; Orlando, Terry; Gustavsson, Simon; Oliver, William | In this talk, we present recent measurements characterizing the propagation of gate errors in a Trotterized quantum algorithm performed using >99.9% fidelity single-qubit and 99.7% fidelity controlled-phase (CZ) gates between flux-tunable transmon qubits. | Session 6: Characterizing Quantum Computing Systems and Components |

114 | Time-Dependent Simulation of Superconducting Quantum Circuits in the Presence of Non-Markovian Noise | Alterman, Sam; Kerman, Andrew | In this presentation, we discuss a quantum trajectory-based dynamics simulation method for such circuits, and present progress towards its use in evaluating residual power dissipation in reversible logic circuits. | Session 6: Characterizing Quantum Computing Systems and Components |

115 | Low Rank Density Matrix Evolution for Noisy Quantum Circuits | Chen, Yi-Ting; Farquhar, Collin; Parrish, Robert | In this work, we present an algorithm for simulating noisy quantum circuits based on the fact that the effective dimensionality of a density matrix is low when the noise level is reasonable small. | Session 6: Characterizing Quantum Computing Systems and Components |

116 | Fast estimation of sparse quantum noise | Harper, Robin; Yu, Wenjun; Flammia, Steven | Here I will present work on a scalable and complete protocol to learn a Pauli channel which only has s non-negligible Pauli error rates. | Session 6: Characterizing Quantum Computing Systems and Components |

117 | Random Circuit Metrics for Performance Assessment and Model Testing | Govia, Luke; Ribeill, Guilhem; Ware, Matthew; Krovi, Hari | Here, we present results on extensions of random circuit metrics to testing error models. | Session 6: Characterizing Quantum Computing Systems and Components |

118 | Benchmarking tools for NISQ systems | McKay, David; Bishop, Lev; Corcoles, Antonio; Jurcevic, Petar; Kandala, Abhinav; Kim, Jin-Sung; Lauer, Isaac; Merkel, Seth; Minev, Zlatko; Sundaresan, Neereja; Srinivasan, Srikanth; Takita, Maika; Wei, Xuan; Sheldon, Sarah; Gambetta, Jay | In this talk I will review the work we are doing at IBM to benchmark NISQ devices and I will discuss our recent results on quantum volume, large-scale entanglement and randomized benchmarking. | Session 6: Characterizing Quantum Computing Systems and Components |

119 | Model Refinement of Noisy Quantum Circuits Using Experimental Characterization | Lilly, Megan; Humble, Travis | We present a test-driven methodology for quantifying QPU performance and characterizing NISQ behavior that offers an alternative to costly experimental characterizations using standard tomographic methods. | Session 6: Characterizing Quantum Computing Systems and Components |

120 | Modeling leakage in superconducting quantum computers | Wudarski, Filip | In this talk, we discuss a potential extension to PC technique, that can in principle take into account leakage to non-computation basis. | Session 6: Characterizing Quantum Computing Systems and Components |

121 | Benchmarking noise with Quantum alternating operator ansatz (QAOA) circuits with a symmetry | Wang, Zhihui; Streif, Michael; Rieffel, Eleanor | We propose adapting a symmetry-preserving QAOA circuit for benchmarking noise. | Session 6: Characterizing Quantum Computing Systems and Components |

122 | Entanglement in superconducting qubits and quantum foundations | Mizel, Ari | With this in mind, we consider the number of particles entangled in certain superconducting qubit states. | Session 6: Characterizing Quantum Computing Systems and Components |

123 | Progress towards high-fidelity CZ gates in a tunable coupling architecture | Quintana, Chris; Satzinger, Kevin; Petukhov, Andre; Chen, Zijun; Mi, Xiao; Chen, Yu | We describe progress towards implementing high-fidelity CZ gates in the Sycamore tunable coupling architecture. | Session 6: Characterizing Quantum Computing Systems and Components |

124 | Understanding Crosstalk in Quantum Processors | Blume-Kohout, Robin; Sarovar, Mohan; Nielsen, Erik; Rudinger, Kenneth; Young, Kevin; Proctor, Timothy | In this talk, I will present a precise and rigorous framework that we have developed for defining and classifying crosstalk errors, and compare it to existing ad hoc definitions. | Session 6: Characterizing Quantum Computing Systems and Components |

125 | Hold the onion: using fewer circuits to characterize your qubits. | Nielsen, Erik; Proctor, Timothy; Rudinger, Kenneth; Sarovar, Mohan; Young, Kevin; Blume-Kohout, Robin | In this talk, we compare the resources required by several QCVV protocols, including gate set tomography (GST) and randomized benchmarking (RB). | Session 6: Characterizing Quantum Computing Systems and Components |

126 | Filter Function Formalism for Unitary Quantum Operations | Hangleiter, Tobias; Cerfontaine, Pascal; Bluhm, Hendrik | Filter Function Formalism for Unitary Quantum Operations | Session 6: Characterizing Quantum Computing Systems and Components |

127 | Detection of coherent noise through the output of random quantum circuits | Kim, Jin-Sung; Bishop, Lev; Corcoles, Antonio; Gambetta, Jay; McKay, David; Merkel, Seth; Smolin, John; Sheldon, Sarah | We present here a method, based on the output of random quantum circuits, capable of quantitatively discriminating coherent noise from incoherent noise in multi-qubit systems. | Session 6: Characterizing Quantum Computing Systems and Components |

128 | Investigating widespread correlated errors in superconducting qubit arrays | McEwen, Matthew; Barends, Rami; Martinis, John | In order to quantify the prevalence of such errors, we take rapid, simultaneous time-resolved measurements of error rates across large numbers of qubits on a single chip. | Session 6: Characterizing Quantum Computing Systems and Components |

129 | Renyi Entropy Benchmarking of Superconducting Qubits | Mi, Xiao; Vermersch, Benoit; Elben, Andreas; Roushan, Pedram; Chen, Yu; Zoller, Peter; Smelyanskiy, Vadim | Motivated by recent progress in trapped ion systems [1], we use sets of random gate unitaries to scramble many-body quantum states and infer their Renyi entropies, which reveal the rate of purity loss of the quantum system. | Session 6: Characterizing Quantum Computing Systems and Components |

130 | Demonstrating Scalable Benchmarking of Quantum Computers | Proctor, Timothy; Rudinger, Kenneth; Young, Kevin; Nielsen, Erik; Blume-Kohout, Robin | In this talk, I will present experimental results demonstrating simple, fast and scalable methods for benchmarking quantum computers. | Session 6: Characterizing Quantum Computing Systems and Components |

131 | Qutrit randomized benchmarking | Morvan, Alexis; Blok, Machiel; Ramasesh, Vinay; chen, Larry; Siddiqi, Irfan | In this talk, we present an experimental implementation of qutrit randomized benchmarking on a 5-qutrit processor. | Session 6: Characterizing Quantum Computing Systems and Components |

132 | Effect of Imperfections on the Cross Entropy Benchmark Fidelity of Random Circuit Sampling | Bao, Yimu; Choi, Soonwon; Altman, Ehud | Here, we present an efficient method to evaluate the amount of average fidelity reduction originating from various kinds of imperfections without any simplifying assumptions. | Session 6: Characterizing Quantum Computing Systems and Components |

133 | Engineering Quantum Process Fidelity via Generalized Markovian Noise | Vlachos, Evangelos; Zhang, Haimeng; Farmer, James; Hartsell, Darian; Levenson-Falk, Eli | Surprisingly, theoretical studies have recently proposed that short-memory (generalized Markovian) noise can be used as a resource to mitigate the effects of Markovian noise. | Session 6: Characterizing Quantum Computing Systems and Components |

134 | Characterizing the performance of NISQ devices with random Clifford circuits | Merkel, Seth; Corcoles, Antonio; Datta, Animesh; Ferracin, Samuele; Kim, Jin-Sung; McKay, David; Sheldon, Sarah | Given this result, we note that a) all of the classical pre/post-processing is efficient and b) we can deal with the variational distance of the output distributions directly without proxies such as the cross entropy or heavy output generation. | Session 6: Characterizing Quantum Computing Systems and Components |

135 | Effects of qubit frequency crowding on scalable quantum processors | Hertzberg, Jared; Rosenblatt, Sami; Chavez, Jose; Magesan, Easwar; Smolin, John; Yau, Jeng-Bang; Adiga, Vivekananda; Brink, Markus; Zhang, Eric; Orcutt, Jason; Chow, Jerry | In this talk we will quantify the effects of frequency crowding and consider how this behavior scales with device size for 50-qubit and larger systems. | Session 6: Characterizing Quantum Computing Systems and Components |

136 | Estimation of statistical significance in the quantum supremacy experiment with the Sycamore processor | Yeh, Ping; Zalcman, Adam; Boixo, Sergio | In this talk, I will describe the methodologies for the statistical analyses and show that the bitstring distributions are extremely unlikely to be explained by noise alone and the fidelity is significantly above the threshold. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

137 | How OpenSuperQ is planning to fully calibrate and characterize a 100 qubit superconducting QPU over the weekend | Machnes, Shai; Wittler, Nicolas; Roy, federico; Saha Roy, Anurag; Pack, Kevin; Wilhelm, Frank | To rectify the situation, we have implemented a novel procedure of Combined Calibration and Characterization (C3): An interative combination of open-loop pulse optimization, model-free tune-up and iterative model fitting and refinement, utilizing a high-performance TensorFlow simulator. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

138 | Advanced Control Calibration for NISQ QPUs and Quantum Devices – Theory and Experiments | Pack, Kevin; Machnes, Shai; Wittler, Nicolas; Roy, federico; Saha Roy, Anurag; Wilhelm, Frank | This talk focuses on the gate calibration task, where optimization algorithms are used to find the best pulse parameter values in a multidimensional space. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

139 | Automatic Calibration and Characterization of Quantum Devices – Experimental Results on NISQ QPUs and Quantum Memory devices | Machnes, Shai; Wittler, Nicolas; Roy, federico; Saha Roy, Anurag; Pack, Kevin; Wilhelm, Frank | By controlling both experiment and a high performance numerical simulation, the C3 procedure provides a framework to systematically design and apply even intricate open loop optimal control pulses. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

140 | Active Learning of Hamiltonians | Dutt, Arkopal; Pednault, Edwin; Wu, Chai; Sheldon, Sarah; Bishop, Lev; Smolin, John; Chuang, Isaac | To this end, we present an efficient active learning algorithm based on Fisher information and assess its performance on recalibrating superconducting qubit systems based on the cross-resonance (CR) gate. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

141 | Optimizing Quantum Gate Frequencies for Google’s Quantum Processors | Klimov, Paul; Kelly, Julian; Satzinger, Kevin; Chen, Zijun; Neven, Hartmut; Martinis, John | In this talk, I will introduce the frequency optimization problem and the Snake optimizer that we developed to solve it for Google’s flagship quantum processors [1]. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

142 | Quantum Orchestration Platform Integrated hardware and software for design and execution of complex quantum control protocols | Cohen, Yonatan; Sivan, Itamar; Ofek, Nissim; Ella, Lior; Drucker, Niv; Shani, Tal; Weber, Ori; Grinberg, Hanan; Greenbaum, Michael | Here we present a new platform for designing quantum control protocols, executing them on a wide range of quantum hardware, and optimizing performance. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

143 | Quantum Orchestration Platform Integrated hardware and software for design and execution of complex quantum control protocols | Sivan, Itamar; Cohen, Yonatan; Ofek, Nissim; Shani, Tal; Weber, Ori; Ella, Lior; Greenbaum, Michael; Grinberg, Hanan; Drucker, Niv | In this talk, we will show examples for quantum-error-correction protocols and demonstrate how they are programmed and run with the QOP. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

144 | High-Fidelity, Scalable Quantum-Classical Control Interface using Photonics | Chan, Jacky; Gowda, Apurva; DeVore, Peter; Buckley, Brandon; DuBois, Jonathan; Chou, Jason | To address this need, we propose an RF-photonic implementation of a QC control interface, via high-fidelity, scalable quantum drive signal generation and fiber optic transport of this signal to the qubit. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

145 | Automatic single qubit characterization with QubiC | Xu, Yilun; Huang, Gang; Naik, Ravi; Mitchell, Bradley; Santiago, David; Siddiqi, Irfan | Based on this feature, we propose a single qubit characterization and gate optimization protocol which automatically find and tune the qubit. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

146 | Optimal Control of Superconducting Qubits | Werninghaus, Max; Egger, Daniel; Roy, federico; Machnes, Shai; Wilhelm, Frank; Filipp, Stefan | Optimal control theory aims to design fast control pulses suppressing such side effects of the driving field. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

147 | Quantum Supremacy: computational complexity and applications | Roushan, Pedram | Here we report the use of a processor with programmable superconducting qubits to create quantum states on 53 qubits. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

148 | Calibration of flux crosstalk in flux qubit based quantum annealers with persistent current readout devices | Dai, Xi; Martinez, Antonio; Tennant, Daniel; Melanson, Denis; Yurtalan, Ali; Bedkihal, Salil; Tang, Yongchao; Melville, Alexander; Niedzielski, Bethany; Das, Rabindra; Kim, David; Yoder, Jonilyn; Weber, Steven; Kerman, Andrew; Novikov, Sergey; Disseler, Steven; Basham, James; Grover, Jeffrey; Mozgunov, Evgeny; Lidar, Daniel; Lupascu, Adrian | We present results on the calibration of flux crosstalk in a device consisting of two flux qubits coupled by a chain of seven couplers. | Session 7: Control and Calibration Tools for Scalable Quantum Computing |

149 | Demonstrating error rate homogenization using dynamically corrected gates in a trapped ion system | Edmunds, Claire; Hempel, Cornelius; Milne, Alistair; Biercuk, Michael | We perform parallel single-qubit operations on a multi-qubit register of 171Yb + ions using a microwave field. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

150 | Error Mitigation Via Simulated Measurement of Stabilizers | Greene, Amy; Kjaergaard, Morten; Schwartz, Mollie; Samach, Gabriel; Bengtsson, Andreas; O’Keeffe, Michael; Marvian, Milad; Winik, Roni; Kim, David; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Rosenberg, Danna; Obenland, Kevin; Orlando, Terry; Marvian, Iman; Oliver, William | We demonstrate the error-mitigating effects of this simulated quantum measurement protocol on a small superconducting qubit processor. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

151 | SPAM Error Correction: Transition Matrix versus Quasiprobabilities | Sun, Mingyu; Geller, Michael | Here apply both methods to online IBM qubits, and find very similar predictions for one- and two-qubit corrected Pauli expectation values, with some indication that the simpler transition matrix method performs slightly better than the quasiprobability representation, at least for the SPAM errors encountered in superconducting qubits. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

152 | Experimental Realization of Randomized Compiling for in-situ Error Reduction | Hashim, Akel; Nowrouzi, Kasra; Morvan, Alexis; Naik, Ravi; Kreikebaum, John Mark; Siddiqi, Irfan | We present work on reducing the average error during the operation of an algorithm through randomized compiling (RC) [1], which tailors arbitrary Markovian noise into stochastic Pauli errors. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

153 | Optimizing stability and performance of cloud-based quantum systems | Sundaresan, Neereja; Lauer, Isaac; Srinivasan, Srikanth; Wang, Cindy; Landers, William; Gordon, Michael; McClure, Douglas | Since the launch of the first five-qubit device on the IBM Q Experience platform in 2016, we have made steady increases in the number of devices available for cloud access, as well as their fidelity, stability, speed and uptime. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

154 | Fidelity of sequences of SWAP operations in chains of multiple coupled qubits | Throckmorton, Robert | We investigate the swapping of qubit states between neighboring qubits in a chain of multiple qubits with quasistatic noise both in the (nearest-neighbor) couplings between them and in fields applied to the individual qubits. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

155 | Noise-resistant Landau-Zener sweeps from geometrical curves | Zhuang, Fei; Zeng, Junkai; Barnes, Edwin; Economou, Sophia | By adapting that formalism, we demonstrate how to design noise-resistant Landau-Zener sweeps through an avoided crossing. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

156 | High-performance nonlinear optimization module for quantum control | Slatyer, Harry; Liebermann, Per; Hush, Michael; Carvalho, André; Ball, Harrison; Gore, Stephen; Biercuk, Michael | In this talk we introduce a custom GPU-compatible optimization toolkit purpose-built for rapidly creating high-fidelity, noise-robust quantum controls in high-dimensional Hilbert spaces. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

157 | Implementation of a canonical phase measurement with quantum feedback | Siddiqi, Irfan | In this work, we implement a single-shot canonical phase measurement on a one-photon wave packet which surpasses the current standard of heterodyne detection and is optimal for single-shot phase estimation. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

158 | Two-qubit Pauli-frame randomization in a superconducting system | Ware, Matthew; Ribeill, Guilhem; Govia, Luke | To remove some of the experimental overhead, we have implemented control system firmware that randomizes quantum circuits on-the-fly using custom control electronics. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

159 | Deep Reinforcement Learning for Quantum Control: Learning to Optimally Navigate in Complex Noisy Environments | Quiroz, Gregory; Titum, Paraj; Schultz, Kevin | Here, we examine how one can leverage reinforcement learning to learn and predict quantum gates in the presence of temporally correlated noise. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

160 | Assigning Hamiltonians to Open Quantum Systems | Dumitrescu, Eugen; Lougovski, Pavel | Building on recent efforts illustrating that one may characterize a closed system of k-local interacting particles, we study the task of identifying a local-Hamiltonian in the presence of additional environmental interactions. | Session 8: Control and Characterization Tools for Quantum Error Mitigation |

161 | Experimental simulation of a two-level open system based on Trotter decomposition | Pan, Xiaoxuan; Han, Jiaxiu; Cai, Weizhou; Hu, Ling; Ma, Yuwei; Xu, Yuan; Mu, Xianghao; Zou, Changling; Sun, Luyan | We demonstrate a hardware-efficient repetitive Trotter scheme of open system simulation, which allows efficient simulation of arbitrary noisy environments for a two-level system. | Session 9: Control and Modelling of Open Quantum Systems |

162 | Arbitrary quantum channel simulations of a superconducting qudit system | Cai, Weizhou; Han, Jiaxiu; Hu, Ling; Ma, Yuwei; Xu, Yuan; Mu, Xianghao; Song, Yipu; Zou, Chang-Ling; Sun, Luyan | In this talk, we will introduce our recent experimental efforts on arbitrary quantum channel simulations of a high dimensional photonic qudit (cavity), with the assistance of a transmon qubit. | Session 9: Control and Modelling of Open Quantum Systems |

163 | Adiabaticity in non-Hermitian dynamics of a superconducting qubit | Chen, Weijian; Abbasi, Maryam; Naghiloo, Mahdi; Joglekar, Yogesh; Murch, Kater | In this talk, I will present our study of adiabaticity in non-Hermitian dynamics of a single dissipative superconducting qubit, where we tune the frequency and amplitude of microwave drives to vary the system Hamiltonian. | Session 9: Control and Modelling of Open Quantum Systems |

164 | Encircling exceptional points of a single dissipative qubit | Abbasi, Maryam; Chen, Weijian; Naghiloo, Mahdi; Hershberger, scott; Joglekar, Yogesh; Murch, Kater | We study the behavior of a single dissipative qubit which is described by a non-Hermitian Hamiltonian. | Session 9: Control and Modelling of Open Quantum Systems |

165 | Dissipative processs to generate entangled state in solid state system | Xin, Wang | Former work has been completed to design the dissipation in many experimental system, for example, ion trap, superconductor and atomic ensembles system. | Session 9: Control and Modelling of Open Quantum Systems |

166 | Shortcuts to adiabaticity in open systems: thermalization of an open quantum oscillator | Chenu, Aurelia; Dupays, Leonce; Egusquiza, Inigo; Del Campo, Adolfo | We introduce STA in open quantum systems, and develop a technique to control the thermalization of a driven open quantum oscillator. | Session 9: Control and Modelling of Open Quantum Systems |

167 | Modeling non-Markovian dynamics with augmented CPTP maps | Young, Kevin; Blume-Kohout, Robin; Bartlett, Stephen | In this talk, we propose a family of augmented CPTP maps that enable simple models of a wide variety of non-Markovian dynamics. | Session 9: Control and Modelling of Open Quantum Systems |

168 | Learning the dynamics of open quantum systems from local measurements | Bairey, Eyal; Guo, Chu; Poletti, Dario; Lindner, Netanel; Arad, Itai | Here, we propose a method for reconstructing the Lindbladian governing the Markovian dynamics of open many-body quantum systems, using data obtained from local measurements on their steady states. | Session 9: Control and Modelling of Open Quantum Systems |

169 | Noise Memory Kernel Reconstruction via the Post-Markovian Master Equation | Zhang, Haimeng; Lidar, Daniel | This talk will present results on the construction of a bath memory kernel function from the experimentally measured state dynamics of a superconducting qubit. | Session 9: Control and Modelling of Open Quantum Systems |

170 | Scalable Bayesian learning of local Hamiltonians and Lindbladian | Evans, Timothy; Harper, Robin; Flammia, Steven | In this talk I will present a Bayesian method that addresses both of these issues by making use of any, or all, of the following: experimental control of Hamiltonian couplings, the preparation of multiple states and the availability of any prior information we may already have for the Hamiltonian couplings. | Session 9: Control and Modelling of Open Quantum Systems |

171 | Parametric Quantum Noise Spectroscopy Using SchWARMA | Schultz, Kevin; Quiroz, Gregory; Clader, David | Here, we adapt techniques from classical time series analysis to model, simulate, and estimate non-Markovian noise. | Session 9: Control and Modelling of Open Quantum Systems |

172 | Experimental Realization of Noise Injection using SchWARMA | Murphy, Andrew; Schultz, Kevin; Epstein, Jacob; McElroy, Kyle; Quiroz, Gregory; Tien-Street, Brian; Hoffmann, Joan; Clader, David; Sweeney, Timothy | We use a technique known as Schrodinger Wave Autoregressive Moving Average (SchWARMA) to mimic phase noise on a qubit. | Session 9: Control and Modelling of Open Quantum Systems |

173 | Continuos feedback of a controllable nonlinear cavity with Deep Reinforcement Learning | Porotti, Riccardo; Zwerger, Michael; Marquardt, Florian | We focus on one of the simplest quantum systems highly relevant for quantum information processing, namely a controllable nonlinear cavity. | Session 9: Control and Modelling of Open Quantum Systems |

174 | Quantum Machine Learning using a Dissipative Quantum Reservoir | Miller, John; Villagran, Martha | Here we discuss the charge density wave (CDW) – a correlated electron-phonon system – as a candidate quantum reservoir. | Session 9: Control and Modelling of Open Quantum Systems |

175 | Decoherence Properties of Qubits and Oscillators Coupled to Minimal Environments | Randles, Kevin; Diaz, David; Van Huele, Jean-Francois; Beus, Ty; Berrondo, Manuel | We relate decoherence rates to coupling strength. | Session 9: Control and Modelling of Open Quantum Systems |

176 | Quantum metrology methods for dark matter searches | Lehnert, Konrad | I will describe the particular case of axionic dark matter, in which superconducting quantum circuits can be used to search for dark matter at a rate exceeding the quantum-limited value. | Session 10: DQI Invited Session: Experimental Advances in Quantum Sensors and Sensing |

177 | Machine learning quantum states in the NISQ era | Melko, Roger | We discuss the development of machine learning techniques for the purpose of reconstructing quantum states from projective measurement data. | Session 11: DQI Invited Session: Machine Learning and Quantum Physics |

178 | About that useful little corner of Hilbert space and its neural network representations | Carleo, Giuseppe | In this talk I will overview a recently introduced classical representation of many-qubit states based on artificial neural networks. | Session 11: DQI Invited Session: Machine Learning and Quantum Physics |

179 | Machine Learning and Quantum | Zhang, Pengfei | Especially, I will describe how to use the idea of active learning to optimize quantum control, which requires minimal number of experimental data. | Session 11: DQI Invited Session: Machine Learning and Quantum Physics |

180 | Machine Learning with Tensor Networks | Stoudenmire, Edwin | I will discuss how a theory of generative modeling of data can be developed in the context of matrix product state models. | Session 11: DQI Invited Session: Machine Learning and Quantum Physics |

181 | The Kerr-Cat Qubit: Stabilization, Readout, and Gates. | Grimm, Alexander | In this talk, we will present our recent experimental results on the stabilization of an error-protected cat qubit through the interplay between Kerr nonlinearity and single-mode squeezing in a superconducting microwave resonator. | Session 12: DQI Invited Session: Quantum Memories for Superconducting Qubits |

182 | Fault-tolerant quantum computation with repetition cat-qubits. | Guillaud, Jeremie; Mirrahimi, Mazyar | We present a 1D repetition code based on the so-called cat-qubits as a viable candidate for a massive reduction in the hardware requirements for universal and fault-tolerant quantum computation. | Session 12: DQI Invited Session: Quantum Memories for Superconducting Qubits |

183 | Detection of optical photons from a superconducting qubit | Sipahigil, Alp | In this talk, we present an integrated device platform for converting a qubit excitation to an optical photon via piezo-optomechanical transduction. | Session 12: DQI Invited Session: Quantum Memories for Superconducting Qubits |

184 | Quantum information processing using multimode cavities | Chakram, Srivatsan | We present various schemes for controlling the cavity states using interactions mediated by the dispersively coupled transmon. | Session 12: DQI Invited Session: Quantum Memories for Superconducting Qubits |

185 | Experimental Demonstration of a Superconducting 0-π Qubit | Gyenis, Andras; Mundada, Pranav; Di Paolo, Agustin; Hazard, Thomas; You, Xinyuan; Schuster, David; Koch, Jens; Blais, Alexandre; Houck, Andrew | We find that the circuit realizes an effective one-dimensional crystal with two sub-lattices, where the geometrical phase difference between Wannier states localized at adjacent phase unit cells leads to interference effects associated with tunneling of pairs of Cooper pairs. | Session 12: DQI Invited Session: Quantum Memories for Superconducting Qubits |

186 | Quantifying high-fidelity state preparation and measurement in triple-quantum-dot qubits | Blumoff, Jacob | In this talk I will discuss implementation of these techniques in isotopically-enriched Si/SiGe triple dots using a direct dot-sensor electrometer with a cryogenic HEMT amplifier. | Session 13: DQI Invited Session: Quantum State Preparation and Measurement (SPAM) in Semiconductor Qubits |

187 | Quantum non-demolition measurement of an electron spin qubit | Yoneda, Jun | In this talk, we show that an electron spin qubit in quantum dots can be measured in a highly non-demolition manner by probing a neighboring electron spin qubit Ising-coupled to the qubit spin. | Session 13: DQI Invited Session: Quantum State Preparation and Measurement (SPAM) in Semiconductor Qubits |

188 | Coherent control of a hybrid superconducting circuit made with van der Waals heterostructures | Oliver, William | In this talk, we present the demonstration of a superconducting transmon qubit realized using a graphene-based weak-link junction. | Session 14: DQI Invited Session: Voltage-Controlled Josephson Junctions in Superconducting Quantum Circuits |

189 | On-chip microwave spectroscopy of Andreev and Majorana bound states in semiconductor nanowires | Geresdi, Attila | In this talk, I will summarize our efforts to understand the Andreev level spectra in proximitized semiconductor nanowires by exploiting the AC Josephson effect and using on-chip microwave detection techniques based on superconducting tunnel junctions. | Session 14: DQI Invited Session: Voltage-Controlled Josephson Junctions in Superconducting Quantum Circuits |

190 | Magnetic-field-compatible hybrid superconducting circuits | Kou, Angela; Pita-Vidal, Marta; Bargerbos, Arno; Yang, Chung-Kai; Van Woerkom, David; Pfaff, Wolfgang; Haider, Nadia; Krogstrup, Peter; Kouwenhoven, Leo; De Lange, Gijs | In this talk, I will discuss our work building a magnetic-field-compatible nanowire-based fluxonium. | Session 14: DQI Invited Session: Voltage-Controlled Josephson Junctions in Superconducting Quantum Circuits |

191 | A ballistic graphene superconducting microwave circuit | Steele, Gary; Schmidt, Felix; Jenkins, mark; Watanabe, Kenji; Taniguchi, Takashi | In this talk, I will present our demonstration of a superconducting microwave circuit based on a ballistic graphene Josephson junction. | |

192 | Coherent Semiconductor-Based Superconducting Quantum Circuits | Petersson, Karl | The recent development of semiconductors with epitaxial superconducting Al contacts offers new approaches to realizing coherent superconducting quantum devices. | |

193 | Electric dipole-induced spin resonance of holes in Ge/Si nanowires | Froning, Florian; Camenzind, Leon; Li, Ang; Bakkers, Erik; Zumbuhl, Dominik; Braakman, Floris | We demonstrate EDSR of hole spins confined in a double quantum dot in a Ge/Si nanowire. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

194 | Electric control of the single hole g-factor by 400% in a silicon MOS quantum dot. | Liles, Scott; Martins, Frederico; Miserev, Dmitry; Thorvaldson, Ian; Rendell, Matthew; Hudson, Fay; Veldhorst, Menno; Sushkov, Oleg; Dzurak, Andrew; Hamilton, Alex | In this work we confine a single hole in a known orbital state [2] and study the Lande g-tensor using a 3D vector magnet. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

195 | Fast and tunable Rabi oscillations of hole spins in Ge/Si nanowires | Froning, Florian; Camenzind, Leon; Li, Ang; Bakkers, Erik; Zumbuhl, Dominik; Braakman, Floris | Fast and tunable Rabi oscillations of hole spins in Ge/Si nanowires | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

196 | Towards scalable hole spin qubits in silicon | Ezzouch, Rami; Zihlmann, Simon; Crippa, Alessandro; Maurand, Romain; Aprà, Agostino; Amisse, Anthony; Jehl, Xavier; Bertrand, Benoit; Hutin, Louis; Vinet, Maud; Venitucci, Benjamin; Li, Jing; Niquet, Yann-Michel; Urdampilleta, Matias; Meunier, Tristan; Sanquer, Marc; De Franceschi, Silvano | Since the first proof-of-concept demonstration of a silicon hole spin qubit based on industry-standard CMOS technology [1], our research efforts have focused on acquiring a better understanding of the mechanism for electric-field-driven hole-spin manipulation [2], as well as on the development of spin readout based on rf gate reflectometry [3]. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

197 | Hole spin echo envelope modulations | Philippopoulos, Pericles; Chesi, Stefano; Salfi, Joe; Rogge, Sven; Coish, William | We give a general theoretical analysis for hole-spin-echo envelope modulation (HSEEM), and apply this analysis to the specific case of a boron-acceptor hole spin in silicon [1]. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

198 | Effects of Valley-Orbit Coupling on the Exchange Interaction in a Si/SiGe Double Quantum Dots | Tariq, Bilal; Hu, Xuedong | We investigate the effects of the phase and magnitude of the valley orbit coupling on the tunnel coupling matrix elements and the exchange interaction in a Si double quantum dot. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

199 | Singlet-triplet splitting of two electrons in a Si/SiGe quantum dot | Ercan, Ekmel; Coppersmith, Susan; Friesen, Mark | We theoretically study the effects of quantum dot confinement strength on the singlet-triplet (ST) splitting of two-electron dots in Si/SiGe quantum wells. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

200 | Operation of a four-qubit device in isotopically enriched Si/SiGe | Sigillito, Anthony; Gullans, Michael; Petta, Jason | Recently, we have demonstrated operation of a four-qubit device in isotopically enriched Si/SiGe [6]. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

201 | Coherent spectroscopy of a Si/SiGe double quantum dot molecule | Baer, Joelle; Dodson, John; Thorgrimsson, Brandur; Ercan, Ekmel; Losert, Merritt; Knapp, Trevor; Holman, Nathan; McJunkin, Thomas; Neyens, Samuel; MacQuarrie, Evan; Foote, Ryan; Edge, Lisa; Friesen, Mark; Coppersmith, Susan; Eriksson, Mark | We present measurements of the broadband spectrum, discovering seven energy levels that can be addressed coherently, each with distinct Rabi oscillation characteristics. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

202 | Towards coupled valley qubits in silicon | Rooney, John; Freeman, Blake; Penthorn, Nicholas; Edge, Lisa; Jiang, HongWen | In this talk, we present our progress on coupling two such valley qubits. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

203 | Hyperfine effects in a single hole GaAs/AlGaAs double quantum dot device | Studenikin, Sergei; Ducatel, Jordan; Korkusinski, Marek; Austing, D.; Zawadzki, Piotr; Sachrajda, Andrew; Philippopoulos, Pericles; Coish, William; Tracy, Lisa; Reno, John; Hargett, Terry | In this work, we detect and explore small DNP effects in a single hole GaAs/AlGaAs gated DQD device using a modified EDSR technique [3]. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

204 | A realistic GaAs-spin qubit device for a classical error-corrected quantum memory and beyond | Rispler, Manuel; Cerfontaine, Pascal; Langrock, Veit; Terhal, Barbara | Based on numerically-optimized real-device gates and parameters we study the performance of the phase-flip (repetition) code on a linear array of GaAs quantum dots hosting singlet-triplet qubits. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

205 | Devloping atom-based solid-state quantum simulators: understanding charge-stability diagrams of dopant arrays in Si | Bryant, Garnett; Townsend, Emily; Wang, Xiqiao; Silver, richard | Here we describe theoretical simulations done for two-dimensional arrays of dopants in Si used to implement an extended range Fermi-Hubbard model. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

206 | Controlling textured hole spins in InAs quantum dots with oscillating electric fields | Lin, Arthur; Doty, Matthew; Bryant, Garnett | Here, we present a reduced Hamiltonian capable of describing the evolution of the lowest hole state tight-binding wavefunctions, simulating the effect of oscillating electric fields, while fully preserving the effects of the spin texture. | Session 15: Electron and Hole Based Spin Qubits in Heterostructures |

207 | State-of-the-art Quantum Dot devices from a full 300mm process line: towards scalable spin qubit devices | George, Hubert C; Bojarski, Stephanie; Pillarisetty, Ravi; Mueller, Brennen; Lampert, Lester; Watson, Thomas; Luthi, Florian; Caudillo, Roman; Michalak, David; Henry, Eric; Zietz, Otto; Roberts, Jeanette; Zwerver, Anne-Marije; Krähenmann, Tobias; Eenink, GertJan; Scappucci, Giordano; Veldhorst, Menno; Vandersypen, Lieven; Clarke, Jim | State-of-the-art Quantum Dot devices from a full 300mm process line: towards scalable spin qubit devices | Session 16: Fabrication of Silicon Qubits |

208 | The impact of using palladium gates for silicon quantum dot fabrication: defect densities and strain | Stein, Ryan; Barcikowski, Zac; Pomeroy, Joshua; Stewart, Michael | Here, we present measurements of oxide defect densities (fixed charge and interface trap density) as a function of forming gas anneal temperature for three different gate metals: Al, Ti/Pd, and Ti/Pt. | Session 16: Fabrication of Silicon Qubits |

209 | Revising the point-charge model for dopants in Si and applications to atomic-scale system simulations | Liu, Keyi; Rozanski, Piotr; Zielinski, Michal; Bryant, Garnett | We have developed a dopant model that includes several new corrections that are obtained explicitly using atomic orbitals to evaluate the appropriate dopant matrix elements rather than by fitting to experiment. | Session 16: Fabrication of Silicon Qubits |

210 | Low-frequency electron spin-qubit detuning noise in highly purified 28Si/SiGe | Struck, Tom; Hollmann, Arne; Schauer, Floyd; Schmidbauer, Andreas; Langrock, Veit; Fedorets, Olexiy; Sawano, Kentarou; Riemann, Helge; Abrosimov, Nikolay; Cywinski, Lukasz; Bougeard, Dominique; Schreiber, Lars | Here, we characterize a 28Si/SiGe device with an embedded nanomagnet, a large valley splitting (> 0.2 meV [2]), and a remaining 29Si concentration of only 60 ppm in the strained silicon quantum well layer, which is grown by molecular beam epitaxy. | Session 16: Fabrication of Silicon Qubits |

211 | Single-electron control in a foundry-fabricated 2D array of silicon quantum dots | Ansaloni, Fabio; Chatterjee, Anasua; Bohuslavskyi, Heorhii; Kuemmeth, Ferdinand | Combining high-frequency reflectometry with pulsed-gate techniques, we tune tunneling rates and demonstrate the shuttling of individual electrons within the two-dimensional array. | Session 16: Fabrication of Silicon Qubits |

212 | Spin Qubits Confined to a Silicon Nano-Ridge | Klos, Jan; Sun, Bin; Beyer, Jacob; Kindel, Sebastian; Hellmich, Lena; Knoch, Joachim; Schreiber, Lars | We propose a scalable qubit device fabricated by industry-compatible processes such as damascene and spacer processes [2]. | Session 16: Fabrication of Silicon Qubits |

213 | Silicon spin qubit development in a 300 mm integrated process | Dumoulin Stuyck, Nard; Li, Roy; Kubicek, Stefan; Mohiyaddin, Fahd; Govoreanu, Bogdan; Elsayed, Asser; Shehata, Mohamed; Jussot, Julien; Chan, BT; Radu, Iuliana; Heyns, Marc | In this talk, we present the integration of Si-MOS spin qubit devices in an hybrid integration scheme, which combines e-beam and optical lithography. | Session 16: Fabrication of Silicon Qubits |

214 | Industrial quantum dot arrays for spin-qubit quantum computation by all-optical 300mm lithography | Krähenmann, Tobias; Zwerver, Anne-Marije; Bojarski, Stephanie; George, Hubert C; Mueller, Brennen; Clarke, Jim; Vandersypen, Lieven | Using quantum dot arrays fabricated in a 300mm process line, we demonstrate well-controlled single and double quantum dots formed in an isotopically enriched 28Si-MOS substrate. | Session 16: Fabrication of Silicon Qubits |

215 | Pauli spin blockade for holes in a hot silicon FinFET | Geyer, Simon; Camenzind, Leon; Warburton, Richard; Zumbuhl, Dominik; Kuhlmann, Andreas | We define single and double QDs in a FinFET-like device architecture. | Session 16: Fabrication of Silicon Qubits |

216 | Crossbar architecture with individually addressable single electron transistors | Bavdaz, Peter; Eenink, GertJan; van Staveren, Job; Almudever, Carmina; Sebastiano, Fabio; Veldhorst, Menno; Scappucci, Giordano | We show experimental effort toward realizing crossbars which are operated using a CMOS multiplexer consisting of commercial components at 50 mK capable of supporting up to 648 SETs. | Session 16: Fabrication of Silicon Qubits |

217 | Silicon quantum dot fabrication with subtractive processing | McJunkin, Thomas; MacQuarrie, Evan; Eriksson, Mark | Here, we present an alternative approach to silicon quantum dot fabrication, utilizing negative-tone e-beam lithography and subtractive processing to replicate the typical three-layer aluminum gate structure with two layers of palladium gates. | Session 16: Fabrication of Silicon Qubits |

218 | Charge and Hybrid Qubits in 22nm FDSOI process | Blokhina, Elena; Giounanlis, Panagiotis; Leipold, Dirk; Bashir, Imran; Asker, Mike; Esmailiyan, Ali; Wang, Hongying; Siriburanon, Teerachot; Sokolov, Andrii; Staszewski, R.Bogdan | This abstract presents the recent development of a quantum system-on-a-chip utilizing quantum structures fabricated in 22nm FDSOI. | Session 16: Fabrication of Silicon Qubits |

219 | Improving Gate Dielectrics for Reducing Charge Noise in Si/SiGe Quantum Dots | Holman, Nathan; Dodson, John; MacQuarrie, Evan; Edge, Lisa; McDermott, Robert; Coppersmith, Susan; Friesen, Mark; Eriksson, Mark | We report on the materials development of a novel low temperature SiO 2 gate dielectric for use in Si/SiGe quantum dot devices. | Session 16: Fabrication of Silicon Qubits |

220 | Charge noise in Si/SiGe quantum dots | Connors, Elliot; Nelson, JJ; Qiao, Haifeng; Nichol, John | Here, we investigate the dependence of low-frequency charge noise spectra on temperature and aluminum-oxide gate dielectric thickness in Si/SiGe quantum dots with overlapping gates. | Session 16: Fabrication of Silicon Qubits |

221 | Readout of fluxonium qubits in circuit QED | Nesterov, Konstantin; Nguyen, Long; Somoroff, Aaron; Ficheux, Quentin; Pechenezhskiy, Ivan; Stevens, Jeremy; Cottet, Nathanael; Huard, Benjamin; Manucharyan, Vladimir; Vavilov, Maxim | In this talk, we present the results of the simulation of the readout process in the fluxonium circuit and discuss how the qubit states and integrated readout signal are affected by the cavity occupation. | Session 17: Fluxonium and Novel Superconducting Qubits |

222 | Microwave-activated entangling gates for fluxonium qubits | Chen, Yinqi; Nesterov, Konstantin; Nguyen, Long; Somoroff, Aaron; Ficheux, Quentin; Pechenezhskiy, Ivan; Manucharyan, Vladimir; Vavilov, Maxim | In this talk, we analyze and compare two-qubit gates between such qubits activated by driving different transitions in the two-qubit spectrum. | Session 17: Fluxonium and Novel Superconducting Qubits |

223 | Single-shot dynamics of fluxonium in the strong dispersive coupling regime | Xiong, Haonan; Lin, Yen-Hsiang; Nguyen, Long; Ficheux, Quentin; Somoroff, Aaron; Manucharyan, Vladimir | We report single-shot measurement of a fluxonium qubit in the strong dispersive regime with maximum coherence time T2>200usec. | Session 17: Fluxonium and Novel Superconducting Qubits |

224 | Fluxonium two-qubit gate with simultaneous Raman transitions | Bryon, Jacob; Vrajitoarea, Andrei; Wang, Yidan; Bienias, Przemyslaw; Lundgren, Rex; Belyansky, Ron; Gorshkov, Alexey; Kollar, Alicia; Houck, Andrew | We propose a new scheme using a cavity to couple two fluxonium qubits and drive a two-qubit swap gate. | Session 17: Fluxonium and Novel Superconducting Qubits |

225 | High Coherence Fluxonium Qubits | Manucharyan, Vladimir | High Coherence Fluxonium Qubits | Session 17: Fluxonium and Novel Superconducting Qubits |

226 | Fast flux qubit gates on a heavy fluxonium | Zhang, Helin; Chakram, Srivatsan; Earnest, Nathan; Lu, Yao; Huang, Ziwen; Weiss, Daniel; Koch, Jens; Schuster, David | Here, we present schemes for state initialization, fast single-qubit flux gates, and plasmon assisted readout for a fluxonium qubit, demonstrating the feasibility of controlling a superconducting qubit at background temperatures much higher than the operating frequency. | Session 17: Fluxonium and Novel Superconducting Qubits |

227 | Spectroscopy and logic gates in a strongly coupled two-fluxonium device | Dogan, Ebru; Rosenstock, Dario; Nguyen, Long; Somoroff, Aaron; Manucharyan, Vladimir; Wang, Chen | Our experimental study focuses on two fluxonium qubits under strong capacitive coupling and we analyze the hybridization of computational states and higher excited states as a function of external flux bias. | Session 17: Fluxonium and Novel Superconducting Qubits |

228 | Fluxonium-like qubit design for improved coherence | Mundada, Pranav; Houck, Andrew; Gyenis, Andras; Huang, Ziwen; Koch, Jens | We present experimental data on the implementation of such a fluxonium-like qubit architecture with extra sweet spots. | Session 17: Fluxonium and Novel Superconducting Qubits |

229 | The Most Coherent Superconducting Qubit? | Somoroff, Aaron; Nguyen, Long; Lin, Yen-Hsiang; Mencia, Ray; Grabon, Nicholas; Ficheux, Quentin; Nesterov, Konstantin; Vavilov, Maxim; Manucharyan, Vladimir | We report superconducting fluxonium qubits with coherence times limited by energy relaxation and reproducibly satisfying T 2 > 100 μs (T 2 > 400 μs in one device). | Session 17: Fluxonium and Novel Superconducting Qubits |

230 | Towards Bell-state stabilization using the Very Small Logical Qubit (VSLQ) device: Part I | Lu, Yao; Roy, Tanay; Kapit, Eliot; Schuster, David | Inspired by previous dissipation-engineering schemes[1,2], we propose an autonomous protocol that prepares and stabilizes an arbitrary Bell state between a pair of superconducting qubits. | Session 17: Fluxonium and Novel Superconducting Qubits |

231 | Towards Bell-state stabilization using the Very Small Logical Qubit (VSLQ) device: Part II | Roy, Tanay; Lu, Yao; Kapit, Eliot; Schuster, David | We report our experimental progress towards the stabilization of an arbitrary Bell-state. | Session 17: Fluxonium and Novel Superconducting Qubits |

232 | Towards high-fidelity quantum operations with fluxonium qubits: Part II-experimental progress | Ku, Hsiang-Sheng; Zhang, Gengyan; Wang, Tenghui; Yu, Wenlong; Deng, Hao; Zhou, Jingwei; Zhang, Yingshan; Sun, Hantao; Song, Zhijun; Zhang, Xiaohang; Tang, Chengchun; Gao, Ran; Xu, Hua; Li, Zhisheng; Qin, Jin; Jiang, Xun; Zhu, Xing; Zhao, Huihai; Wu, Feng; Ding, Dawei; Deng, Chunqing | In this talk, we present the experimental progresses on developing fluxonium quantum processors. | Session 17: Fluxonium and Novel Superconducting Qubits |

233 | Towards high-fidelity quantum operations with fluxonium qubits: Part I-design and simulation | Ku, Hsiang-Sheng; Zhang, Gengyan; Wang, Tenghui; Yu, Wenlong; Deng, Hao; Zhou, Jingwei; Zhang, Yingshan; Sun, Hantao; Song, Zhijun; Zhang, Xiaohang; Tang, Chengchun; Gao, Ran; Xu, Hua; Li, Zhisheng; Qin, Jin; Jiang, Xun; Zhu, Xing; Zhao, Hui-Hai; Wu, Feng; Ding, Dawei; Deng, Chunqing | In the talk, we present the design of fluxonium quantum processors. | Session 17: Fluxonium and Novel Superconducting Qubits |

234 | Tunable Current Mirror Qubits: Experimental Status | Wenner, James; Khalil, Moe; Weiss, Daniel; Koch, Jens; Ferguson, David | This talk also describes design optimizations of current-mirror qubits, and gives a status report on coherence tests, including tests that utilize adiabatic protection sweeps. | Session 17: Fluxonium and Novel Superconducting Qubits |

235 | Phase-shift flux qubit with a ferromagnetic π junction | Yamashita, Taro; Zuo, Kun; Urade, Yoshiro; Qiu, Wei; Terai, Hirotaka; Fujimaki, Akira; Nakamura, Yasunobu | In this talk, we will discuss the NbN-Al hybrid fabrication process and the results of the spectroscopy and time-domain measurements. | Session 17: Fluxonium and Novel Superconducting Qubits |

236 | Electrically-tunable phase-slip qubits | Kenawy, Ahmed; Magnus, Wim; Soree, Bart | Here, we investigate the possibility of using a voltage-biased superconducting ring to realize a phase-slip qubit. | Session 17: Fluxonium and Novel Superconducting Qubits |

237 | Influence of charge fluctuations on Josephson phase-slip qubits | Hirjibehedin, Cyrus; Weber, Steven; Samach, Gabriel; Kim, David; Melville, Alexander; Niedzielski, Bethany; Rosenberg, Danna; Serniak, Kyle; Yoder, Jonilyn; Oliver, William; Kerman, Andrew | We characterize the influence of charge fluctuations on the JPSQ, examining both discrete quasiparticle tunneling as well as drifts and jumps in the background charge offset. | Session 17: Fluxonium and Novel Superconducting Qubits |

238 | Bifluxon: Fluxon-Parity-Protected Superconducting Qubit | Kalashnikov, Konstantin; Hsieh, Wen Ting; Zhang, Wenyuan; Lu, Wen-Sen; Kamenov, Plamen; Di Paolo, Agustin; Blais, Alexandre; Gershenson, Michael; Bell, Matthew | We have developed and characterized a symmetry-protected superconducting qubit that offers simultaneous exponential suppression of energy decay from both the charge and flux noise, and dephasing from flux noise [1]. | Session 17: Fluxonium and Novel Superconducting Qubits |

239 | Blochnium: A flux-tunable qubit with flux-insensitive coherence times | Mencia, Ray; Pechenezhskiy, Ivan; Nguyen, Long; Lin, Yen-Hsiang; Manucharyan, Vladimir | We introduce a flux-insensitive superconducting artificial atom nicknamed “blochnium", which is dual to a transmon. | Session 17: Fluxonium and Novel Superconducting Qubits |

240 | Novel Qubit Designs | Ioffe, Lev | Novel Qubit Designs | Session 17: Fluxonium and Novel Superconducting Qubits |

241 | Rabi Oscillations in a Superconducting Nanowire Circuit | Schön, Yannick; Voss, Jan Nicolas; Wildermuth, Micha; Schneider, Andre; Skacel, Sebastian; Weides, Martin; Cole, Jared; Rotzinger, Hannes; Ustinov, Alexey | We investigate the circuit quantum electrodynamics of superconducting nanowire oscillators. | Session 17: Fluxonium and Novel Superconducting Qubits |

242 | Ultrastrong coupling to parasitic modes in superconducting circuits with hyperinductors | Pechenezhskiy, Ivan; Mencia, Ray; Kuzmin, Roman; Nguyen, Long; Lin, Yen-Hsiang; Manucharyan, Vladimir | Ultrastrong coupling to parasitic modes in superconducting circuits with hyperinductors | Session 17: Fluxonium and Novel Superconducting Qubits |

243 | Relaxation and decoherence of 2D fluxonium | Bharadwaj, Karthik Srikanth; Foroughi, Farshad; Dumur, Etienne; Planat, Luca; Ranadive, Arpit; Naud, Cécile; Buisson, Olivier; Roch, Nicolas; Hasch-Guichard, Wiebke | In this work we coupled the fluxonium qubit to on-chip lumped element and distributed resonators. | Session 17: Fluxonium and Novel Superconducting Qubits |

244 | A Rotary Echo Flux Qubit | Sirota, Alexander; Ferguson, David; Schuster, David; Epstein, Ryan | This talk describes a qubit that utilizes a rotary echo control technique to maintain long T1 times yet also generating insensitivity to flux noise below a cutoff frequency. | Session 17: Fluxonium and Novel Superconducting Qubits |

245 | Characterization and control of topologically protected charge-parity qubits: Part 1 | Dodge, Kenneth; Liu, Yebin; Senatore, Michael; Naveen, FNU; Zhu, Shaojiang; Shearrow, Abigail; Klots, Andrey; Faoro, Lara; Ioffe, Lev; McDermott, Robert; Plourde, Britton | Here, we will describe our experimental characterization of one- and two-plaquette devices through spectroscopy and time-domain measurements. | Session 17: Fluxonium and Novel Superconducting Qubits |

246 | Characterization of topologically protected charge-parity qubits: Part 2 | Naveen, FNU; Shearrow, Abigail; Zhu, Shaojiang; Dodge, Kenneth; Liu, Yebin; Senatore, Michael; Klots, Andrey; Faoro, Lara; Ioffe, Lev; Plourde, Britton; McDermott, Robert | We describe the design and characterization of a plaquette-based qubit with an embedded SQUID switch. | Session 17: Fluxonium and Novel Superconducting Qubits |

247 | Conditional teleportation of quantum dot spin states | Nichol, John | Here, we present a conditional quantum teleportation protocol for electron spin qubits in semiconductor quantum dots. | Session 18: Focus Entanglement in Quantum Dot Arrays |

248 | Rydberg blockade entangling gates in silicon | Crane, Eleanor; Schuckert, Alexander; Le, Nguyen; Fisher, Andrew | In this work, we show how this constraint can be released by using Rydberg blockade entangling gates between orbital excited states of donors, which are robust against variations in the interaction strength. | Session 18: Focus Entanglement in Quantum Dot Arrays |

249 | Entanglement of encoded spin-qubits via curvature couplings to a superconducting cavity | Ruskov, Rusko; Tahan, Charles | We propose entangling operation and preparation procedures based on curvature couplings of encoded spin qubits to a superconducting cavity, exploring the non-linear qubit response to a voltage variation. | Session 18: Focus Entanglement in Quantum Dot Arrays |

250 | Far-detuned two-qubit operation of the quantum-dot hybrid qubit coupled to a microwave resonator | Abadillo-Uriel, Jose Carlos; King, Cameron; Coppersmith, Susan; Friesen, Mark | In this work, we explore this far-detuned regime. | Session 18: Focus Entanglement in Quantum Dot Arrays |

251 | Coherent transport of spin by adiabatic passage in quantum dot arrays | Gullans, Michael; Petta, Jason | We develop the theoretical framework of spin-CTAP using the Heisenberg exchange interaction in a linear array of quantum dots. | Session 18: Focus Entanglement in Quantum Dot Arrays |

252 | Robust two-qubit entangling gates using shaped pulses in silicon double quantum dots | Gungordu, Utkan; Kestner, Jason | We consider a device working in this regime, with always-on exchange coupling, and describe how a CZ gate and arbitrary one-qubit gates which are robust against charge noise can be implemented by smoothly pulsing the microwave source, while eliminating the crosstalk stroboscopically. | Session 18: Focus Entanglement in Quantum Dot Arrays |

253 | Democratizing Spin Qubits | Tahan, Charles | I’ve been building Powerpoint-based quantum computers with electron spins in silicon for 19 years. | Session 18: Focus Entanglement in Quantum Dot Arrays |

254 | Fabrication and Measurement of Arrays of Few-Donor Quantum Dots | Silver, Rick; Wang, Xiqiao; Kashid, Ranjit; Rigosi, Albert; Wyrick, Jonathan; Fei, Fan; Namboodiri, Pradeep | Here, we extend the STM-patterning method to fabricate coupled arrays of few atom clusters having multiple donors per dot, including a functional 3×3 quantum dot array device. | Session 18: Focus Entanglement in Quantum Dot Arrays |

255 | Realizing Discrete Time Crystals in Quantum Dot Spin Arrays with Magnetic Field Gradients | Li, Bikun; Van Dyke, John; Warren, Ada; Economou, Sophia; Barnes, Edwin | Previous work showed that it is possible to realize this phase in quantum dot spin arrays with nearest-neighbor exchange interactions if the number of pulses per period is substantially increased. | Session 18: Focus Entanglement in Quantum Dot Arrays |

256 | Exploring Many-body Localization in Quantum Dot Systems | Li, Bikun; Van Dyke, John; Warren, Ada; Economou, Sophia; Barnes, Edwin | We theoretically investigate the realization of many-body localized phases in a quantum dot system, the latter naturally yielding the nearest-neighbor Heisenberg model subject to a magnetic field gradient. | Session 18: Focus Entanglement in Quantum Dot Arrays |

257 | Fine-tuning electron entanglement in two-dimensional artificial atoms | Pham, Dung; Bharadwaj, Sathwik; Ram-Mohan, L | We obtain the spatial entanglement values for a wide range of two-dimensional quantum dots with varying potentials. | Session 18: Focus Entanglement in Quantum Dot Arrays |

258 | Operating four singlet-triplet qubits in a two-dimensional array of GaAs dots | Fedele, Federico; Chatterjee, Anasua; Fallahi, Saeed; Gardner, Geoff; Manfra, Michael; Kuemmeth, Ferdinand | Here we present the simultaneous coherent manipulation and readout of a two-by-two singlet-triplet qubit array in GaAs, with a large multielectron dot coupler at the center. | Session 18: Focus Entanglement in Quantum Dot Arrays |

259 | Strong photon coupling to the quadrupole moment of an electron in a triple quantum dot | Koski, Jonne; Landig, Andreas; Russ, Maximilian; Abadillo-Uriel, Jose Carlos; Scarlino, Pasquale; Kratochwil, Benedikt; Reichl, Christian; wegscheider, werner; Burkard, Guido; Coppersmith, Susan; Wallraff, Andreas; Ensslin, Klaus; Ihn, Thomas | We demonstrate strong electron-photon coupling via the quadrupole moment in a parameter regime with negligible dipole coupling. | Session 19: Focus Exchange Based Spin Qubits |

260 | Efficient orthogonal control of tunnel couplings in a quantum dot array | Hsiao, Tzu-Kan; van Diepen, Cornelis; Mukhopadhyay, Uditendu; Reichl, Christian; wegscheider, werner; Vandersypen, Lieven | Here we show that the crosstalk on tunnel barriers can be compensated using a linear combination of gate voltages, since the exponential dependence applies to all gates. | Session 19: Focus Exchange Based Spin Qubits |

261 | Barrier-Controlled Multi-Qubit Exchange | Qiao, Haifeng; Kandel, Yadav; Fallahi, Saeed; Gardner, Geoff; Manfra, Michael; Nichol, John | In this work we demonstrate simultaneous control of multiple barrier-induced exchange couplings in a four-qubit processor. | Session 19: Focus Exchange Based Spin Qubits |

262 | Coherent Spin-State Transfer via Heisenberg Exchange | Kandel, Yadav; Qiao, Haifeng; Fallahi, Saeed; Gardner, Geoffrey; Manfra, Michael; Nichol, John | Here we present the first experimental demonstration of the coherent transfer of electron spin states back and forth across a chain of four quantum-dot spin qubits using Heisenberg exchange coupling between neighboring electrons, which arises from the overlap of their wavefunctions. | Session 19: Focus Exchange Based Spin Qubits |

263 | Noise-resilient driven exchange gate for quantum dot spin qubits | Philips, Stephan; Russ, Maximilian; Vandersypen, Lieven | We propose a simple yet effective scheme that is resilient against low-frequency charge noise. | Session 19: Focus Exchange Based Spin Qubits |

264 | Interplay of exchange and superexchange in triple quantum dots | Deng, Kuangyin; Barnes, Edwin | We will describe our theoretical efforts to understand the controllability of superexchange interactions in these systems. | Session 19: Focus Exchange Based Spin Qubits |

265 | Coherent manipulation of three-spin states in a Si/SiGe triple quantum dot | Takeda, Kenta; Noiri, Akito; Nakajima, Takashi; Yoneda, Jun; Kobayashi, Takashi; Tarucha, Seigo | In this work, we demonstrate coherent manipulation of three individual spins in a Si/SiGe triple quantum dot by site-selective electric dipole spin resonance. | Session 19: Focus Exchange Based Spin Qubits |

266 | Full Permutation Dynamical Decoupling in an Encoded Triple-Dot Qubit | Sun, Bo | Using gate-defined quantum dots in an enriched Si/SiGe device, we demonstrate that repeated applications of the full permutation sequence can echo low frequency charge and magnetic noise, resulting a dynamically decoupled coherence time of 100s of microseconds. | Session 19: Focus Exchange Based Spin Qubits |

267 | Highly tunable exchange-only singlet-only qubit in a GaAs triple quantum dot | Sala, Arnau; Qvist, Jørgen; Danon, Jeroen | Here we propose an implementation of this singlet-only qubit in a triple quantum dot with a (1,4,1) charge occupation. | Session 19: Focus Exchange Based Spin Qubits |

268 | Correcting Distortion of Base-band Exchange Pulses in Quantum Dot Qubits | Barnes, David | Here we present a technique to correct the known distortion of our arbitrary waveform generators. | Session 19: Focus Exchange Based Spin Qubits |

269 | Long-Distance Charge Transport in a Single Electron Conveyor Device in (Al,Ga)As | Kuenne, Matthias; Trellenkamp, Stefan; Ritzmann, Julian; Ludwig, Arne; Wieck, Andreas; Bluhm, Hendrik | In this talk, I will present a device designed to allow the shuttling of electrons over 7 µm with only four voltage signals, whereby in principle arbitrary distances are feasible. | Session 19: Focus Exchange Based Spin Qubits |

270 | Computer-automated tuning procedures for semiconductor quantum dot arrays | Mills, Adam; Feldman, Mayer; Monical, Cara; Lewis, Phillip; Larson, Kurt; Mounce, Andrew; Petta, Jason | By automating the analysis of charge stability diagrams, we can easily create tools to tune charge occupancy and interdot tunnel couplings in our quantum dot arrays. | Session 19: Focus Exchange Based Spin Qubits |

271 | Designing CPHASE Gates with Arbitrary Phase by Structural Modification of the Fong-Wandzura Sequence | Zeuch, Daniel; Bonesteel, Nicholas | The construction we present is motivated by our analytic derivation [1] of the Fong-Wandzura sequence [2], the shortest known pulse sequence for an exact CNOT gate (for a linear array of spins). | Session 19: Focus Exchange Based Spin Qubits |

272 | Readout of small-scale semiconductor spin-qubit arrays | Chatterjee, Anasua | I will present our work on readout techniques and scaling efforts, in particular involving RF-reflectometry, in small two-dimensional arrays of quantum dots in GaAs and silicon. | Session 20: Focus Semiconductor Spin Qubit Readout |

273 | Cascade-Based Fast, High-Fidelity and Scalable Spin Readout | van Diepen, Cornelis; Hsiao, Tzu-Kan; Mukhopadhyay, Uditendu; Reichl, Christian; wegscheider, werner; Vandersypen, Lieven | Here, we report on cascade-based fast, high-fidelity and scalable spin readout. | Session 20: Focus Semiconductor Spin Qubit Readout |

274 | Fast charge sensing in undoped silicon quantum dots with radio-frequency reflectometry | Noiri, Akito; Takeda, Kenta; Yoneda, Jun; Nakajima, Takashi; Kodera, Tetsuo; Tarucha, Seigo | To this end, we introduce a specially designed device geometry comprising a small accumulation gate area [3]. | Session 20: Focus Semiconductor Spin Qubit Readout |

275 | Rapid high-fidelity spin state readout in Si/SiGe quantum dots via radio-frequency reflectometry | Nelson, JJ; Connors, Elliot; Nichol, John | Here we will present minor design changes that when implemented in a Si/SiGe quantum dot device enable charge readout fidelity above 99.9% in 300ns using rf reflectometry. | Session 20: Focus Semiconductor Spin Qubit Readout |

276 | Repetitive Quantum Nondemolition Measurement of a Silicon Spin Qubit Using Different Decodings | Xue, Xiao; D’Anjou, Benjamin; Watson, Thomas; Ward, Dan; Savage, Donald; Lagally, Max; Friesen, Mark; Coppersmith, Susan; Eriksson, Mark; Coish, William; Vandersypen, Lieven | We compare the two methods and discuss the conditions for which soft decoding provides an advantage. | Session 20: Focus Semiconductor Spin Qubit Readout |

277 | Single-shot single-electron spin readout with a single-lead quantum dot charge sensor | Hogg, Mark; Timofeev, Andrey; Pakkiam, Prasanna; Gorman, Samuel; House, Matthew; Simmons, Michelle | Here we demonstrate a dispersively-probed single-lead quantum dot (SLQD) charge sensor which senses the charges on four quantum dots, each defined with P atoms in Si using scanning tunnelling microscope lithography. | Session 20: Focus Semiconductor Spin Qubit Readout |

278 | Theory of Pulsed Spectroscopy in Quantum Dots: Interdot Dynamics | Pan, Andrew | We have developed a technique to characterize these quantities using typical tune-up conditions, relying on the incoherent dynamics of interdot charge transitions. | Session 20: Focus Semiconductor Spin Qubit Readout |

279 | Pulsed Spectroscopy of Si/SiGe Quantum Dots: One- and Two-Electron Valley-Orbit Excited States | Raach, Kate | In the second half of this two-part talk, we present experimental data and analysis of this energy structure using pulsed techniques to simultaneously probe multiple valley and orbital states of double quantum dots. | Session 20: Focus Semiconductor Spin Qubit Readout |

280 | Developing Monolithic Superconducting Resonators for Gate-Based Quantum Dot Readout | Barcikowski, Zac; Stewart, Michael; Bal, Mustafa; Richardson, Christopher; Pappas, David; Pomeroy, Joshua | We present transmission and reflection data used to assess our ability to deterministically fabricate resonators with designed inductance and capacitance values. | Session 20: Focus Semiconductor Spin Qubit Readout |

281 | Non-Markovian qubit spectroscopy in cavity QED | McIntyre, Zoé; Coish, William | Motivated by very recent work showing strong coupling of spin/charge qubits coupled to superconducting microwave resonators, we use a generalized input-output theory to account for a generic non-Markovian environment. | Session 20: Focus Semiconductor Spin Qubit Readout |

282 | Low-magnetic field single-spin qubit operation in isotopically enriched silicon | ZHAO, RUICHEN; Tanttu, Tuomo; Tan, Kuan Yen; Hensen, Bas; Chan, Kok; Hwang, Jason; Leon, Ross; Yang, Chih-Hwan; Gilbert, Will; Hudson, Fay; Itoh, Kohei; Kiselev, Andrey; Ladd, Thaddeus; Morello, Andrea; Laucht, Arne; Dzurak, Andrew | Here we present an alternative scheme where we use high-fidelity Pauli spin blockade readout to enable single-spin qubit operation in a magnetic field as low as 150mT. | Session 20: Focus Semiconductor Spin Qubit Readout |

283 | Adiabatic conversion for qubit readout: Optimal pulse shapes and dephasing | Fehse, Felix; Pioro-Ladriere, Michel; Coish, William | We give an explicit construction that allows for optimal state conversion in qubit readouts. | Session 20: Focus Semiconductor Spin Qubit Readout |

284 | Machine Learning-Based control of 2D Arrays of Quantum Dots | Izadi Rad, Ali; Kalantre, Sandesh; Taylor, Jacob; Zwolak, Justyna | In this project, we extend a recent proposal [3,4] of employing a ML-based auto-tuner to linear QD devices to the more general case of 2D arrays. | Session 20: Focus Semiconductor Spin Qubit Readout |

285 | RuleSet-based Operation of the Quantum Internet | Van Meter, Rodney | RuleSet-based Operation of the Quantum Internet | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

286 | Resource-efficient quantum communication using all-photonic graph states generated from quantum emitters | Hilaire, Paul; Barnes, Edwin; Economou, Sophia | Here, we consider using quantum emitters to produce the graph states and show how the resource/performance trade-off can be optimized to yield a protocol that outperforms both repeaterless and memory-based schemes. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

287 | Stable Polarization Entanglement based Quantum Key Distribution over Metropolitan Fibre network | shi, yicheng; Soe, Moe Thar; Poh, Hou Shun; Grieve, James; Kurtsiefer, Christian; Ling, Alexander | We demonstrate a Quantum key distribution (QKD) system implemented with polarisation-entangled photons over telecom fibre network. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

288 | Experimental Study of an Elementary Cryogenic Microwave Quantum Network | Magnard, Paul; Kurpiers, Philipp; Lütolf, Janis; Marxer, Fabian; Storz, Simon; Schär, Josua; Wallraff, Andreas | In this talk, we present an experimental study of essential elements of a cryogenic quantum network. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

289 | Rapid transfer of a qubit state into a microwave pulse using a notch Purcell filter | Sunada, Yoshiki; Kono, Shingo; Ilves, Jesper; Tamate, Shuhei; Tabuchi, Yutaka; Nakamura, Yasunobu | We report our progress on analyzing the filter performance and the fidelity of the state transfer. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

290 | A genuine quantum router for microwave photons | Wang, Zhiling; Bao, Zenghui; Wu, Yukai; Zhang, Hongyi; Song, Yipu; Duan, Luming | In this talk, I will introduce our experiments of realizing a genuine quantum router in the microwave domain based on superconducting circuit quantum electrodynamics system and demonstrate the coherent routing of a microwave quantum state with high fidelity using a transmon qubit. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

291 | Quantum communication networks with superconducting qubits | Zhong, Youpeng; Bienfait, Audrey; Chang, Hung-Shen; Chou, Ming-Han; Conner, Christopher; Dumur, Etienne; Grebel, Joel; Povey, Rhys; Schuster, David; Cleland, Andrew | In this talk, we examine the scalability of this architecture, and explore more complex quantum communication network designs and protocols. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

292 | Unidirectional emitter and receiver of an itinerant microwave photon in an open waveguide | Gheeraert, Nicolas; Kono, Shingo; Nakamura, Yasunobu | Here, we theoretically demonstrate unidirectional emission and absorption of an itinerant microwave photon in an open waveguide using a unit consisting of two superconducting qubits that are parametrically coupled to the waveguide via transfer resonators a quarter-wavelength apart. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

293 | Error-detected state transfer and entanglement in a superconducting quantum network: Part 1 | Teoh, James; Burkhart, Luke; Zhang, Yaxing; Axline, Christopher; Frunzio, Luigi; Devoret, Michel; Jiang, Liang; Girvin, Steven; Schoelkopf, Robert | This talk will discuss how this flexible operation can be used for bidirectional state transfer and entanglement generation between modules. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

294 | Error-detected state transfer and entanglement in a superconducting quantum network: Part 2 | Burkhart, Luke; Teoh, James; Zhang, Yaxing; Axline, Christopher; Frunzio, Luigi; Devoret, Michel; Jiang, Liang; Girvin, Steven; Schoelkopf, Robert | We use a quantum bus to transfer qubits and generate entanglement across a two-node network. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

295 | Josephson-Photonics Devices as a Source of Entangled Microwave Photons | Dambach, Simon; Peugeot, Ambroise; Leppäkangas, Juha; Kubala, Björn; Westig, Marc; Ménard, Gerbold; Mukharsky, Yuri; Altimiras, Carles; Roche, Patrice; Joyez, Philippe; Vion, Denis; Esteve, Daniel; Portier, Fabien; Ankerhold, Joachim | In this talk, we present a detailed theoretical study of the bipartite entanglement between photon pairs in the output transmission lines. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

296 | Superconducting Qubits for Robust Remote Entanglement via Adiabatic State Transfer | Chang, Hung-Shen; Zhong, Youpeng; Bienfait, Audrey; Chou, Ming-Han; Conner, Christopher; Dumur, Etienne; Grebel, Joel; Peairs, Gregory; Povey, Rhys; Satzinger, Kevin; Cleland, Andrew | We demonstrate that in the limit of low loss, an adiabatic passage method performs as well as previously demonstrated relay method [1], while in the presence of strong loss, the adiabatic passage achieves states transfer and entanglement fidelities more than a factor of two larger than the relay method. | Session 21: Focus Session on Modular, Distributed Quantum Computing: Hardware |

297 | Multiplexing quantum modules in computational and communication systems. | Nemoto, Kae | In this talk, we focus on these unique features of distributed quantum information processing and give a few examples of how we can implement various protocols and architecture for quantum computation and communications with an NV-based quantum module. | Session 22: Focus Session on Modular, Distributed Quantum Computing: Protocols and Architecture Design |

298 | Designing Scalable Quantum Network Architectures | Suchara, Martin; Chung Miranda, Joaquin; Kettimuthu, Rajkumar; Kolar, Alexander; Wu, Xiaoliang; Zhong, Tian | In this work we use simulations to quantify the performance of networks with quantum router and repeater nodes. | Session 22: Focus Session on Modular, Distributed Quantum Computing: Protocols and Architecture Design |

299 | Routing in a quantum network | Munro, William; Lo Piparo, Nicolo; Hanks, Michael; Nemoto, Kae | It is important to characterize the performance of the various approaches and so we introduce various cost metrics associated with the resources used within the repeaters nodes to normalize our communication rates by. | Session 22: Focus Session on Modular, Distributed Quantum Computing: Protocols and Architecture Design |

300 | A novel approach towards designing and structuring Quantum Communication devices and Quantum information processing. | Chinchole, Aditya | A modified quantum information processing system is also stated in this paper. | |

301 | Towards inter-city entanglement generation using solid state spins in diamond. | Stolk, Arian; Morits, Jaco; Zwet, Erwin; Hagen, Ronald; Verlaan, Ad; Weaver, Matthew; Hanson, Ronald | In this talk I will show latest experimental progress towards generating entanglement between two Dutch cities via 30km of fibre. | |

302 | Entanglement Certification in Witness Experiments with Arbitrary Noise | Dirkse, Bas; Pompili, Matteo; Hanson, Ronald; Walter, Michael; Wehner, Stephanie | In this work, we derive a method to certify entanglement without putting any assumptions on the state at each trial. | |

303 | Scalability Analysis Of Atomic Ensemble Based Quantum Repeaters Using The NetSquid Simulator | Maier, David; Rabbie, Julian; Rozpedek, Filip; Avis, Guus; Coopmans, Tim; Dahlberg, Axel; Torres, Ariana; de Jong, Walter; Nijsten, Loek; Papendrecht, Martijn; de Oliveiro Filho, Julio; Elkouss, David; Knegjens, Rob; Wehner, Stephanie | For the purpose of a scalability analysis we investigate the performance of different architectures using atomic-ensemble technology in a large repeater chain spanning hundreds of kilometers. | |

304 | Verifiable Hybrid Secret Sharing With Few Qubits | Lipinska, Victoria; Murta, Gláucia; Ribeiro, Jeremy; Wehner, Stephanie | We propose a protocol that achieves this task, while reducing the number of required qubits, as compared to the existing protocols. | |

305 | Deterministic entanglement between non-interacting systems with linear optics | Martin, Leigh; Whaley, Birgitta | Measurement-based heralded entanglement schemes provide the primary method to entangle physically separated nodes in most quantum systems. | |

306 | Protocols for creating and purifying GHZ states | de Bone, Sebastian; Ouyang, Runsheng; Goodenough, Kenneth; Elkouss, David | In particular, we introduce an algorithm based on dynamical programming to optimize over a large class of protocols that create and purify GHZ states. | |

307 | Constraints on continuous variable entanglement swapping in the presence of photon loss | Kwiatkowski, Alex; Shojaee, Ezad; Glancy, Scott; Knill, Emanuel | In the presence of sufficient photon loss, which we model as a fictitious beamsplitter with the environment on each of the two modes, we show that such a measurement cannot be used to swap entanglement. | |

308 | Quantum Control through Optical Nonlinearities for Error Corrected One-way Quantum Repeaters | Krastanov, Stefan; Heuck, Mikkel; Jacobs, Kurt; Narang, Prineha; Englund, Dirk | We present how the couplings between multiple optical modes, mediated by material nonlinearities, enable the performance of error correction and logical operations for a number of small bosonic error correcting codes. | |

309 | Entanglement of a pair of quantum emitters under continuous fluorescence measurements | Lewalle, Philippe; Elouard, Cyril; Kizhakkumpurath Manikandan, Sreenath; Qian, Xiao-Feng; Eberly, J; Jordan, Andrew | We examine the state and entanglement dynamics of two remote qubits, under continuous measurements of their spontaneous emission. | |

310 | Si based quantum computer architecture and associated engineering challenges | Vinet, Maud; Mortemousque, Pierre-Andre; Hutin, Louis; Bertrand, Benoit; Jehl, Xavier; Niquet, Yann-Michel; Pillonnet, Gaël; Billiot, Gérard; Sanquer, Marc; Jadot, Baptiste; Chanrion, Emmanuel; Urdampilleta, Matias; Meunier, Tristan | In this presentation, we will share our quantum accelerator architecture and will present progress made towards the actual demonstration of this architecture. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

311 | A Valley Hot-Spot Driven Singlet-Triplet Qubit in a Silicon MOS DQD | Jock, Ryan; Jacobson, Noah; Rudolph, Martin; Ward, Dan; Carroll, Malcolm; Luhman, Dwight | Here, we present a novel operating mode of a singlet-triplet qubit that exploits an inter-valley SO interaction to drive high-orthogonality, electrical-only qubit control. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

312 | Learning the states of double quantum dot systems: A ray-based approach | Zwolak, Justyna; McJunkin, Thomas; Kalantre, Sandesh; Neyens, Samuel; MacQuarrie, Evan; Edge, Lisa; Eriksson, Mark; Taylor, Jacob | Now we expand on this work and propose a novel approach where we use 1D traces (“rays”) measured in multiple directions in the gate voltage space to describe the position of the features characterizing each state (i.e., to “fingerprint” the state space). | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

313 | Spin shuttling in a silicon double quantum dot | Ginzel, Florian; Mills, Adam; Petta, Jason; Burkard, Guido | Motivated by the demand[1] for long and intermediate range interaction in quantum information devices and recent developments[2,3] we theoretically analyze the dynamics of an electron during a detuning sweep in a silicon double quantum dot (DQD) occupied by one electron, and investigate possibilities and limitations of spin transport. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

314 | Towards an electrically controlled spin-valley quantum dot qubit in silicon | Penthorn, Nicholas; Rooney, John; Schoenfield, Joshua; Edge, Lisa; Jiang, HongWen | Using real-time spin relaxation measurements on a single electron in this device with a variable external field, we see evidence of spin-valley mixing signified by a “hot spot” with high spin relaxation below 500 mT. Additionally, we show our progress on implementing valley-mediated spin qubit operations. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

315 | Charge noise induced spin decoherence in a double quantum dot: Effects of a micromagnet | Zhao, Xinyu; Hu, Xuedong | Our results present a systematic approach to study decoherence processes caused by charge noise, particularly for quantum dots in an inhomogeneous magnetic field. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

316 | Universal quantum logic in hot silicon qubits | Eenink, Harmen; Petit, Luca; Russ, Maximilian; Lawrie, William; Hendrickx, Nico; Clarke, Jim; Vandersypen, Lieven; Veldhorst, Menno | Demonstrating qubit operation at elevated temperatures would therefore be a major breakthrough in the effort towards scalable quantum systems. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

317 | Intel Spin Qubits: Automated low-temperature measurement and statistical data analysis for improved fabrication and device design | Caudillo, Roman; Luthi, Florian; Lampert, Lester; Watson, Thomas; Michalak, David; Henry, Eric; Amin, Payam; George, Hubert C; Bojarski, Stephanie; Mueller, Brennen; Pillarisetty, Ravi; Roberts, Jeanette; Clarke, Jim | Here we present an automated approach to tuning up quantum dots and extracting gate crosstalk, charging energy (E c), leverarm, charge noise, and other device performance metrics, which are then fed back to device design and the fabrication process for iterative improvements in performance. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

318 | Intel Quantum Dot Devices: temperature dependence of electrical characteristics and correlating noise measurements for improved measurement turn-around | Luthi, Florian; Caudillo, Roman; Watson, Thomas; Lampert, Lester; Zietz, Otto; George, Hubert C; Bojarski, Stephanie; Mueller, Brennen; Amin, Payam; Henry, Eric; Michalak, David; Pillarisetty, Ravi; Roberts, Jeanette; Clarke, Jim | Intel Quantum Dot Devices: temperature dependence of electrical characteristics and correlating noise measurements for improved measurement turn-around | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

319 | Fabrication process and failure analysis for robust quantum dots in silicon | Dodson, John; Holman, Nathan; Thorgrimsson, Brandur; Neyens, Samuel; MacQuarrie, Evan; Foote, Ryan; McJunkin, Thomas; Edge, Lisa; Coppersmith, Susan; Eriksson, Mark | We present low-temperature oxidation techniques for a thicker aluminum oxide with breakdown voltages of over 4 volts, reducing the risk of damage due to ESD and gate-to-gate leakage. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

320 | Simplified MOS Quantum Dots for Materials Characterization | Pomeroy, Joshua; Ramanayaka, Aruna; Hong, Yanxue; Tang, Ke; Stein, Ryan; Stewart, Michael | Simplified MOS Quantum Dots for Materials Characterization | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

321 | Development of simulator for silicon quantum dot devices based on semiclassical device modeling | Asai, Hidehiro; Iizuka, Shota; Hattori, Junichi; Ikegami, Tsutomu; Fukuda, Koichi; Mori, Takahiro | In this presentation, we report our recent development of a prototype simulator which can simulate the basic characteristics of silicon quantum dot devices as a basis of spin qubit. | Session 23: Focus Silicon Spin Qubits in Double Quantum Dots |

322 | Novel Trotter formulas for digital quantum simulation | Liu, Yi-Xiang; Hines, Jordan; Li, Zhi; Ajoy, Ashok; Cappellaro, Paola | In this talk, I will introduce a geometric framework for optimizing the order of operations without considering the details of the operations themselves, thus achieving computational efficiency. | Session 24: General Quantum Algorithms |

323 | Quantum Simulation of Quantum Field Theory with Qubit Models | Buser, Alex; Bhattacharya, Tanmoy; Chandrasekharan, Shailesh; Singh, Hershdeep; Gupta, Rajan | We consider a class of qubit models which can be simulated efficiently on a fault-tolerant quantum computer, and present evidence that these models possess a rich phase diagram. | Session 24: General Quantum Algorithms |

324 | Quantum Simulation of Nonlinear Classical Dynamics | Joseph, Ilon; Castelli, Alessandro; DuBois, Jonathan; Geyko, Vasily; Graziani, Frank; Libby, Stephen; Parker, Jeffrey; Rosen, Yaniv; Shi, Yuan | Quantum Simulation of Nonlinear Classical Dynamics | Session 24: General Quantum Algorithms |

325 | Predicting Features of Quantum Systems from Very Few Measurements | Huang, Hsin-Yuan; Kueng, Richard; Preskill, John | We present an efficient approach for constructing an approximate classical description, called the classical shadow, of a quantum system from very few quantum measurements that can later be used to predict a large collection of features. | Session 24: General Quantum Algorithms |

326 | Characterizing quantum phase transitions by the entanglement of high symmetric points: A quantum computational investigation | Xiao, Xiao; Kemper, Alexander | Here we demonstrate that the entanglement of a small subset of a product state can be used as an indicator for quantum phase transitions. | Session 24: General Quantum Algorithms |

327 | CnNOT gates for implementing random quantum walks | Soufargi, Selim; Ben Slimen, Iyed; gueddana, amor; Lakshminarayanan, Vasudevan | Based on the outputs, we highlight the physical constraints behind the real backend results and give numerical approximations for the errors for higher qubit number systems. | Session 24: General Quantum Algorithms |

328 | Isolated Vertices in Continuous-Time Quantum Walks on Dynamic Graphs | Wong, Thomas | In this paper, we permit isolated vertices to be loopless or looped, and loopless isolated vertices do not evolve at all under the quantum walk. Using this distinction, we construct simpler dynamic graphs that implement the Pauli gates and a set of universal quantum gates consisting of the Hadamard, $T$, and CNOT gates, and these gates are easily extended to multi-qubit systems. | Session 24: General Quantum Algorithms |

329 | Enhancing Quantum Linear System Algorithm by Richardson Extrapolation | Carrera Vazquez, Almudena; Frisch, Albert; Steenken, Dominik; Barowski, Harry; Hiptmair, Ralf; Woerner, Stefan | We present a complete implementation of the HHL algorithm to solve tridiagonal Toeplitz systems of linear equations of size N with Ο(log(N)log 3(1/ε)+log(κ)λ min/ε) gates, where ε is the accuracy, κ the condition number and λ min the smallest eigenvalue, an exponential improvement in the size of the system over classical methods. | Session 24: General Quantum Algorithms |

330 | Universality and conformal invariance in hybrid quantum circuits | Li, Yaodong; Chen, Xiao; Ludwig, Andreas; Fisher, Matthew P | We establish the emergence of conformal field theories (CFT) in (1+1)-dimensional hybrid quantum circuits right at the measurement-driven entanglement transition, by revealing the remarkable space-time conformal covariance of entanglement entropies and mutual information, computed numerically for various subregions at all time steps within Clifford circuits of up to L = 512 qubits and T = 1024 time steps. | Session 24: General Quantum Algorithms |

331 | Time Complexity Reduction for Gate-Model Quantum Computers | Gyongyosi, Laszlo; Imre, Sandor | A method is defined for the time complexity reduction of near-term gate-model quantum computers. | Session 24: General Quantum Algorithms |

332 | Green’s functions of molecules using a quantum computer | Kosugi, Taichi; Matsushita, Yuichiro | Given the recent rapid development of techniques for quantum computation of electronic structures[1], we propose an algorithm for the construction of one-particle Green’s function (GF) of an interacting electronic system via statistical sampling on a quantum computer for quantum chemistry. | Session 24: General Quantum Algorithms |

333 | Quantum Phase Estimation with Time-Frequency Qudits in a Single Photon | Hu, Zixuan; lu, Hsuan-Hao; Alshaykh, Mohammed; Moore, Alexandria; Wang, Yuchen; Imany, Poolad; Weiner, Andrew; Kais, Sabre | In this work, we report an experimental realization of a qudit-based PEA on a photonic platform, utilizing the high dimensionality in time and frequency degrees of freedom (DoFs) in a single photon. | Session 24: General Quantum Algorithms |

334 | Implementing single-qubit POVMs on a circuit-based quantum computer | Yordanov, Yordan | We present a deterministic protocol to implement general single-qubit POVMs on near-term circuit-based quantum computers. | Session 24: General Quantum Algorithms |

335 | Renyi and Tsallis entropies of the Aharonov-Bohm ring in uniform magnetic fields | Olendski, Oleg | Renyi and Tsallis entropies of the Aharonov-Bohm ring in uniform magnetic fields | Session 24: General Quantum Algorithms |

336 | Coherent storage of microwave photons over 100ms in an ensemble of electron spins. | Flurin, Emmanuel; Rajan, Vishal; Albertinale, Emanuele; Esteve, Daniel; Bertet, Patrice | Here we report the coupling of a small ensemble of \approx 10^4 Bismuth donors in silicon to a superconducting micro-resonator at a clock-transition, at millikelvin temperatures. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

337 | Optomechanically induced selective emitter—emitter interactions for control of quantum networks | Neuman, Tomas; Trusheim, Matthew; Wang, Derek; Harris, Isaac; Narang, Prineha | Here we suggest a coupling scheme where optically active qubits (e.g. artificial atoms in diamond) of different excitation frequencies are dispersively coupled to a shared mode of an optical cavity. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

338 | Optically hyperpolarized nanodiamonds: quantum control and avenues for signal-enhanced NMR | Ajoy, Ashok; Druga, Emanuel; Lv, Xudong; Meriles, Carlos; Reimer, Jeffrey; Pines, Alexander | I will describe quantum-assisted modalities to deliver signal enhancements in conventional MRI and NMR mediated by quantum defects in nanodiamond powder. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

339 | Design and fabrication of large-scale diamond quantum memories in hybrid photonic circuits | Lu, Tsung-Ju; Wan, Noel; Chen, Kevin; Walsh, Michael; Trusheim, Matthew; De Santis, Lorenzo; Bersin, Eric; Harris, Isaac; Mouradian, Sara; Bielejec, Edward; Englund, Dirk | Here, we describe the design, fabrication, and integration of diamond quantum micro-chiplets containing single SiV and GeV centers with photonic integrated circuits (PICs). | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

340 | Characterizing a 72-channel defect-free array of diamond quantum memories in a photonic integrated circuit | Wan, Noel; Lu, Tsung-Ju; Chen, Kevin; Walsh, Michael; Trusheim, Matthew; De Santis, Lorenzo; Bersin, Eric; Harris, Isaac; Mouradian, Sara; Bielejec, Edward; Englund, Dirk | In a previous abstract, we described the unity creation, coupling and integration of diamond "artificial atoms" of silicon vacancy (SiV) and germanium vacancy (GeV) centers with a large-scale photonic integrated circuit (PIC) in aluminum nitride. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

341 | Nanophotonic Quantum Registers based on Silicon Vacancy Centers in Diamond | Knall, Erik; Bhaskar, Mihir; Nguyen, Christian; Riedinger, Ralf; Machielse, Bartholomeus; Levonian, David; Stroganov, Pavel; Sukachev, Denis; Park, Hongkun; Loncar, Marko; Lukin, Mikhail | In this talk, I will discuss how interfacing with nearby nuclear spins as well as improved device design and fabrication continue to push this system’s capabilities as a platform for foundational demonstrations of memory based quantum communication. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

342 | Coupling an Inverted Spin Ensemble to a Microwave Resonator | Ball, Jason; Moroshkin, Peter; Norimoto, Shota; Konstantinov, Denis; Kubo, Yuimaru | Using an ensemble of nitrogen (P1) centers in diamond placed inside a 3-D loop-gap resonator, we observe population inversion of a satellite P1 transition when a microwave pump tone is applied to the central P1 transition. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

343 | Coherent coupling of V[TCNE]x≈2 magnons to NV center spins | Candido, Denis; Fuchs, Gregory; Flatté, Michael | Here, we calculate the magnon spectrum, fringe fields and magnetizations profiles for V[TCNE] x≈2 disks. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

344 | Cavity mediated interactions and strong entanglement between YIG samples without using intrinsic nonlinearities. | Muttathil Prabhakarapada Nair, Jayakrishnan; Agarwal, Girish | In particular we present a novel scheme to generate an entangled pair of yttrium iron garnet (YIG) samples in a cavity system. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

345 | Improving coupling strengths and lifetimes in quantum magnonics | Lachance-Quirion, Dany; Wolski, Samuel; Tabuchi, Yutaka; Kono, Shingo; Sunada, Yoshiki; Usami, Koji; Nakamura, Yasunobu | Improving coupling strengths and lifetimes in quantum magnonics | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

346 | High frequency ferromagnetic spectroscopy enabled by coupling pairs of magnons to NV spins | McCullian, Brendan; Thabt, Ahmed; Gray, Benjamin; Melendez, Alex; Wolf, Michael; Safonov, Vladimir; Pelekhov, Denis; Bhallamudi, Vidya; Page, Michael; Hammel, P Chris | We have used NV relaxometry to detect driven ferromagnetic dynamics in a low-damping insulating ferrimagnet, nickel zinc aluminum ferrite. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

347 | Electrical switching of spin-magnon interaction | Solanki, Abhishek; Bogdanov, Simeon; Rustagi, Avinash; Dilley, Neil; Shen, Tingting; Debashis, Punyashloka; Chen, Zhihong; Appenzeller, Joerg; Chen, Yong; Shalaev, Vladimir; Upadhyaya, Pramey | In this work, we demonstrate electrical tuning of the coupling between spin waves and electron spins of nitrogen-vacancy centers (NV) in diamond. | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

348 | Optical quantum nondemolition measurement of a solid-state spin without a cycling transition | Thompson, Jeff | Optical quantum nondemolition measurement of a solid-state spin without a cycling transition | Session 25: Hybrid Systems – Diamond Color Centers, Magnonics |

349 | Strong-coupling physics with semiconductor spin qubits | Petta, Jason | Here we combine a large electric-dipole interaction with spin-orbit coupling to achieve spin-photon coupling. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

350 | Control and readout of superconducting qubits over optical fiber using cryogenic photonic links | Teufel, John; Quinlan, Franklyn; Lecocq, Florent; Diddams, Scott; Aumentado, Jose | In this talk we will present recent experimental progress toward the control and readout of a superconducting qubit using microwave signals transmitted over optical fiber to the ultracryogenic environment (< 20 mK), and show proof of principle results that this novel method can meet the stringent requirements for superconducting quantum information processing. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

351 | A Lithium Niobate Electro-Optic Transducer for Quantum Networks | McKenna, Timothy; Witmer, Jeremy; Patel, Rishi; Herrman, Jason; Jiang, Wentao; Arrangoiz-Arriola, Patricio; Wollack, Edward; Van Laer, Raphael; Safavi-Naeini, Amir | We present the design and experimental demonstration of an electro-optic photon converter to connect superconducting qubit-based systems with light. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

352 | Microwave-to-optical transduction in a silicon-organic-hybrid platform | Witmer, Jeremy; McKenna, Timothy; Arrangoiz-Arriola, Patricio; Wollack, Edward; Patel, Rishi; Van Laer, Raphael; Safavi-Naeini, Amir | Here, we present progress towards electro-optic photon conversion using a silicon-organic hybrid photonic platform. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

353 | Dispersive sensing of electron tunneling between quantum dots in proximitized InAs nanowires | De Jong, Damaz; Waardenburg, Daan; Blaznik, Nejc; Han, Lin; Malinowski, Filip; Prosko, Christian; Van Veen, Jasper; Krogstrup, Peter; Kouwenhoven, Leo; Pfaff, Wolfgang | Here, we demonstrate tunneling between two quantum dots separated by a superconducting island realized in an InAs nanowire, partially proximitized by Al. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

354 | A gate-tunable, field-compatible fluxonium | Pita-Vidal, Marta; Bargerbos, Arno; Yang, Chung-Kai; Van Woerkom, David; Pfaff, Wolfgang; Haider, Nadia; Krogstrup, Peter; Kouwenhoven, Leo; De Lange, Gijs; Kou, Angela | Here, we present a new hybrid circuit: a magnetic-field compatible fluxonium with an electrostatically-tuned semiconducting nanowire as its non-linear element. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

355 | Dynamics and manipulation of a trapped, superconducting quasiparticle: Part 1/2 | Fatemi, Valla; Hays, Max; Bouman, Daniël; Serniak, Kyle; Diamond, Spencer; Connolly, Tom; De Lange, Gijs; Krogstrup, Peter; Nygård, Jesper; Geresdi, Attila; Devoret, Michel | In this first part of a joint presentation, we will present the background, experimental setup, and a theoretical model for our system. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

356 | Dynamics and manipulation of a trapped, superconducting quasiparticle: Part 2/2 | Hays, Max; Fatemi, Valla; Bouman, Daniël; Serniak, Kyle; Diamond, Spencer; Connolly, Tom; De Lange, Gijs; Krogstrup, Peter; Nygård, Jesper; Geresdi, Attila; Devoret, Michel | We will present our experimental platform demonstrating large spin-dependent dispersive shifts of a microwave resonator. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

357 | Resonant phenomena in a microchannel-confined Wigner solid | Beysengulov, Niyaz; Lane, Justin; Rees, David; Nasyedkin, Kostyantyn; Stefanski, Taryn; Dykman, Mark; Pollanen, Johannes | We present new experimental results on the resonant response of electrons on helium confined in a single microchannel device and subjected to RF irradiation. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

358 | Dynamical coupling of surface acoustic waves to electrons on helium | Byeon, Heejun; Nasyedkin, Kostyantyn; Beysengulov, Niyaz; Lane, Justin; Bi, Baokang; Pollanen, Johannes | We report on the dynamical coupling between high-frequency piezoelectric surface acoustic waves (SAWs) and a two-dimensional (2D) system of electrons floating on liquid helium. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

359 | Dispersive readout of qubit states: towards realizing spin qubits using electrons on helium | KAWAKAMI, ERIKA; Elarabi, Asem; Konstantinov, Denis | Recently, we propose and experimentally demonstrate a new readout technique for the hydrogen-like quantized states (Rydberg states) of many electrons on helium [3]. | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

360 | Integrating superfluids with superconducting qubit systems | Lane, Justin; Tan, Dian; Beysengulov, Niyaz; Nasyedkin, Kostyantyn; Brook, Evan; Zhang, Liangji; Stefanski, Taryn; Byeon, Heejun; Murch, Kater; Pollanen, Johannes | We find that the cavity, the qubit, and their coupling are all modified by the superfluid, which we analyze within the framework of circuit quantum electrodynamics (cQED). | Session 26: Hybrid Systems – Electro-Optics, Superconductors, & Helium |

361 | Entanglement of Microwave-Optical Modes in a Strongly Coupled Electro-Optomechanical System | Han, Xu; Zhong, Changchun; Jiang, Liang | In Part A: We introduce frequency entanglement in the strongly coupled electro-optomechanical system and discuss the experimental detection scheme. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

362 | Entanglement of Microwave-Optical Modes in a Strongly Coupled Electro-Optomechanical System | Zhong, Changchun; Han, Xu; Jiang, Liang | Based on a generic strongly coupled cavity electro-optomechanical system, we study the microwave-optical entanglement generation and quantify the frequency entanglement between the two modes. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

363 | Ground state cooling and high-fidelity quantum transduction via parametrically-driven bad-cavity optomechanics | Lau, Hoi-Kwan; Clerk, Aashish | In this work, we propose a simple but powerful method based on cavity parametric driving to suppress the unwanted excitation that does not require working with a deeply sideband-resolved cavity. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

364 | Mechanical Purcell Filter for Microwave Quantum Machines | Cleland, Agnetta; Pechal, Marek; Stas, Pieter-Jan; Sarabalis, Christopher; Arrangoiz-Arriola, Patricio; Wollack, Edward; Jiang, Wentao; McKenna, Timothy; Safavi-Naeini, Amir | In this talk, we propose and analyze design for a mechanical Purcell filter, composed of an array of nanomechanical resonators in thin-film lithium niobate, whose frequencies are chosen to produce a bandpass response. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

365 | Microwave-frequency acoustic resonators with high quality factors | Chou, Ming-Han; Dumur, Etienne; Peairs, Gregory; Bienfait, Audrey; Chang, Hung-Shen; Conner, Christopher; Grebel, Joel; Povey, Rhys; Satzinger, Kevin; Zhong, Youpeng; Cleland, Andrew | In this talk, we describe the design and fabrication of mechanical resonators comprising suspended hybrid structures combining aluminum nitride and silicon supported by a phononic crystal, providing mechanical isolation with an integrated piezoelectric transduction mechanism. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

366 | A multimode nonlinear resonator for quantum acoustics | Andersson, Gustav; Jolin, Shan; Scigliuzzo, Marco; Delsing, Per | We introduce a Kerr nonlinearity to a SAW resonator by integrating a SQUID (Superconducting QUantum Interference Device) into one of the Bragg reflectors. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

367 | Existence of a new surface mode with transverse electric field | Wang, Zongye; Hu, Xuedong | Here we report the study of a surface mode in a piezoelectric material with transverse electric field, which has not been explored in previous studies of surface acoustic waves. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

368 | Optimal control of nanomechanical quantum memory coupled to superconducting qubit | Kang, Mingyu; Wang, Zhaoyou; Wollack, Edward; Cleland, Agnetta; Gruenke, Rachel; Lee, Nathan; Multani, Kevin; Pechal, Marek; Arrangoiz-Arriola, Patricio; Safavi-Naeini, Amir | In this work we explore the optimal control for performing high-fidelity state preparation and unitary gates on quantum memory by using a power- and bandwidth-limited pulse optimization method. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

369 | Synthesizing multi-phonon quantum superposition states using three-body interactions with transmon qubits | Kounalakis, Marios; Blanter, Yaroslav; Steele, Gary | We propose a scheme for controlling a radio-frequency mechanical resonator at the quantum scale using two superconducting transmon qubits. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

370 | Nonclassical energy squeezing with quadratic electromechanics | Ma, Xizheng; Viennot, Jeremie; Kotler, Shlomi; Teufel, John; Lehnert, Konrad | In this number squeezed state, we observe a striking feature of the quadratic coupling, the two phonon recoils of the mechanical oscillator due to qubit transitions. | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

371 | Computing with Quantum Analogues | Runge, Keith; Hasan, M.; Calderin, Lazaro; Lata, Trevor; Lucas, Pierre; Deymier, Pierre | Computing with Quantum Analogues | Session 27: Hybrid Systems – Electromechanics, Optomechanics |

372 | Long-distance entangling gates between quantum dot spins mediated by a superconducting resonator | Economou, Sophia | I will present our work on high-fidelity quantum gates, both between spin qubits in neighboring QDs and between remote QDs coupled through a resonator mode. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

373 | Resonant Microwave Mediated Interactions Between Distant Electron Spins | Borjans, Felix; Croot, Xanthe; Mi, Xiao; Gullans, Michael; Petta, Jason | We demonstrate resonant microwave-mediated coupling between two electron spins that are physically separated by more than 4 mm [4]. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

374 | Interfacing epitaxial rare earth spins with superconducting circuits for high-sensitivity ESR | Johnson, Noah; Gupta, Shobhit; Pei, Yuxiang; Singh, Manish Kumar; Guha, Supratik; Schuster, David; Zhong, Tian; Yang, Jun; Zhang, Haitao | We report on pulsed and continuous wave ESR spectroscopy measurements of erbium dopants in Y 2O 3 [4] performed at millikelvin temperature using a microwave resonator. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

375 | High-Speed Quantum Interface with a Quantum Dot Molecule Coupled to a Superconducting Resonator | Tsuchimoto, Yuta; Sun, Zhe; Togan, Emre; Knüppel, Patrick; Delteil, Aymeric; Fält, Stefan; Kroner, Martin; Ensslin, Klaus; Wallraff, Andreas; wegscheider, werner; Imamoglu, Atac | We fabricate an onchip hybrid device consisting of a QDM and a SC resonator and demonstrate a large MW coupling strength. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

376 | On-chip superconducting resonator devices for sensitive spin detection at high magnetic fields. | Franco-Rivera, Giovanni; Cochran, Josiah; Chen, Lei; Wang, Zhen; Bertaina, Sylvain; Chiorescu, Irinel | The ability to probe spin-photon interactions using Electron Spin Resonance techniques has gained significant interest given the realization of hybridized states between microwave photons and different spin ensembles. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

377 | Theory of spin-orbit mediated hole spin-photon coupling in lateral Ge/SiGe quantum dots | Srinivasa, Vanita; Lewis, Rupert; Tracy, Lisa; Lu, Tzu-Ming; Hardy, Will; Brickson, Mitchell; Baczewski, Andrew; Luhman, Dwight | We present an analytical formulation of heavy hole spin-photon coupling mediated by spin-orbit interaction in lateral Ge/SiGe quantum dots. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

378 | High kinetic inductance superconducting cavity for strong coupling of Si/SiGe qubits | Palma, Mario; Holman, Nathan; Neyens, Samuel; MacQuarrie, Evan; Edge, Lisa; Friesen, Mark; Coppersmith, Susan; McDermott, Robert; Eriksson, Mark | We present a Si/SiGe quantum dot device that combines a high impedance cavity and low impedance leads to reduce the photon leakage through the DC lines. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

379 | Coupling silicon qubits via a high-impedance superconducting resonator | Harvey-Collard, Patrick; zheng, guoji; Dijkema, Jurgen; Samkharadze, Nodar; Brousse, Delphine; Carrasco, F.; Sammak, Amir; Scappucci, Giordano; Vandersypen, Lieven | Here, I will describe our experimental efforts to couple two spin qubits through a superconducting microwave resonator. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

380 | Sensitive spin detection using differential squids and on chip microwave waveguide | Cochran, Josiah; Franco-Rivera, Giovanni; Chen, Lei; Wang, Zhen; Chiorescu, Irinel | A novel differential squid detection method for spin systems on a microwave waveguide is being developed at NHMFL. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

381 | From Transistors to Circuit Realization of a 50mK Analog Amplifier in FDSOI Technology For Measuring Quantum-Dots | Le Guevel, Loïck; Billiot, Gérard; Tagliaferri, Marco; Zurita, Marcos; De Franceschi, Silvano; Sanquer, Marc; Vinet, Maud; Jehl, Xavier; Jansen, Aloysius; Pillonnet, Gaël | From Transistors to Circuit Realization of a 50mK Analog Amplifier in FDSOI Technology For Measuring Quantum-Dots | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

382 | 3D integrated device architecture for hybrid superconductor-semiconductor quantum dot devices | Schupp, Felix; Croot, Xanthe; Borjans, Felix; Mi, Xiao; Rosenberg, Danna; Das, Rabindra; Kim, David; Melville, Alexander; Oliver, William; Petta, Jason | Here we present a 3D integrated super-semi architecture with the superconducting resonator chip fabricated in an environment optimized for superconducting qubits and then flip-chip bonded onto a spin-qubit chip fabricated in its own dedicated facility. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

383 | Quantum physics with pulses of radiation | Molmer, Klaus | I shall present a new (and simple) theoretical formalism [1] that accounts for the interaction of travelling pulses of quantized radiation with a local quantum system such as a qubit, a spin or a multi-level atom in a cavity. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

384 | Quantum optical characterization of rare earth ion in superconductor quantum memory | Nayfeh, Osama | We present characterization in the cryogenic regime of a rare earth ion quantum memory we formed from ion implantation of Neodymium ions in superconducting Niobium Nd 3+:Nb. | Session 28: Hybrid Systems – Spins, Quantum Dots, Microwaves |

385 | Sensing and transduction with high-Q micromechanical membranes | Regal, Cindy | I will present experiments probing micromechanical motion at quantum limits using SiN membranes. | Session 29: Hybrid/Macroscopic Quantum Systems, Optomechanics, and Interfacing AMO with Solid State/Nano Systems |

386 | Improved optical cavity in microwave-mechanical-optical transducer | Urmey, Maxwell; Brubaker, Benjamin; Mittal, Sarang; Burns, Peter; Kindem, Jonathan; Lehnert, Konrad; Regal, Cindy | By redesigning the optical cavity, we have reduced misalignment-induced optical loss and enabled greater optomechanical coupling, allowing reduced pump powers. | Session 29: Hybrid/Macroscopic Quantum Systems, Optomechanics, and Interfacing AMO with Solid State/Nano Systems |

387 | Toward on-chip microwave to optical transduction using erbium doped crystals | Rochman, Jake; Xie, Tian; Bartholomew, John; Craiciu, Ioana; Kindem, Jonathan; Schwab, Keith; Faraon, Andrei | Here, we present our progress towards a REI-based transducer using superconducting microwave resonators and amorphous silicon photonic crystal resonators patterned on the surface of an erbium-doped yttrium orthovanadate crystal. | Session 29: Hybrid/Macroscopic Quantum Systems, Optomechanics, and Interfacing AMO with Solid State/Nano Systems |

388 | Constructing Perfect Quantum Transducers Using Multi-Mode Imperfect Transducers | Zhang, Mengzhen; Chowdhury, Shoumik; Jiang, Liang | In this work, we generalize the previous results and show how to transform generic multi-mode imperfect transducers into perfect transducers requiring only finite-squeezing resources, based on a general protocol of decoupling irrelevant bosonic modes from the original system. | |

389 | A compact trampoline-in-the-middle system for acoustic frequency quantum optomechanics | Pluchar, Christian; Agrawal, Aman; Schenk, Edward; Wilson, Dalziel | We present a technique to “load” the resonator into the cavity by radiation pressure feedback cooling. | |

390 | Reducing added-noise in a micro-mechanically mediated electro-optic converter | Mittal, Sarang; Brubaker, Benjamin; Urmey, Maxwell; Burns, Peter; Kindem, Jonathan; Regal, Cindy; Lehnert, Konrad | Here, we present our efforts to lower the added noise by designing phononic shielding of the mechanics and replacing our superconducting metal with NbTiN. | |

391 | Towards quantum optomechanics using bulk acoustic wave resonators | Doeleman, Hugo; Vollenweider, Silvan; von Lüpke, Uwe; Chu, Yiwen | We present our advances in developing a cryogenic cavity optomechanical device based on a bulk-acoustic-wave (BAW) mechanical resonator, which can act as an essential part of a MW-to-optical transducer. | |

392 | Towards entanglement and interconversion of single mm-wave and optical photons in a hybrid cavity-QED system with Rydberg atoms | Suleymanzade, Aziza; Stone, Mark; Taneja, Lavanya; Anferov, Alexander; Kalia, Jasmine; Schuster, David; Simon, Jonathan | I will present our most recent progress towards entangling and interconverting single millimeter wave (mm-wave) and optical photons using Rydberg atoms as a transducer. | |

393 | Large electromechanical coupling in inductively coupled electromechanics | Schmidt, Philip; Amawi, Mohammad; Weichselbaumer, Stefan; Schwienbacher, Daniel; Pogorzalek, Stefan; Marx, Achim; Gross, Rudolf; Huebl, Hans | Here, we demonstrate electromechanical coupling based on a partly suspended SQUID combined with a coplanar microwave resonator exceeding a coupling rate of 1 kHz. | |

394 | Laser cooling to the zero-point energy of a nanomechanical oscillator | Qiu, Liu; Shomroni, Itay; Seidler, Paul; Kippenberg, Tobias | Here, we demonstrate continuous-wave laser sideband cooling of a silicon optomechanical crystal to the zero-point energy, reaching a mean thermal occupancy of $0.09_{-0.01}^{+0.02}$ quanta, or 92\% ground state occupation, self-calibrated via motional sideband asymmetry. | |

395 | Strong magnetomechanical coupling Part 1 | Kirchmair, Gerhard; Zoepfl, David; Schneider, Christian; Juan, Mahtieu | In our ongoing experimental efforts to reach this single-photon strong coupling regime, we developed an approach based on a mechanical oscillator inductively coupled to a superconducting circuit. | |

396 | Strong magnetomechanical coupling Part 2 | Schneider, Christian; Zoepfl, David; Juan, Mathieu; Kirchmair, Gerhard | In our ongoing experimental efforts to reach this single-photon strong coupling regime, we developed an approach based on a mechanical oscillator inductively coupled to a superconducting circuit. | |

397 | Exploring synthetic quantum matter in superconducting circuits | Ma, Ruichao | I will present our recent results on a new approach for preparing photonic many-body phases, where engineered dissipation is used as a resource to protect the fragile quantum states against intrinsic losses [1]. | |

398 | Listening to Bulk Crystalline Vibrations with Superconducting Qubits | Jain, Vijay; Yoon, Taekwan; Lei, Chan U; Chu, Yiwen; Frunzio, Luigi; Rakich, Peter; Schoelkopf, Robert | Here, we use the lifetime of a superconducting qubit to measure the local density of acoustic states in sapphire as a proxy for electro-mechanical decoherence. | |

399 | Strong coupling of two individually controlled atoms via a nanophotonic cavity | Ocola, Paloma; Samutpraphoot, Polnop; Dordevic, Tamara; Bernien, Hannes; Senko, Crystal; Vuletic, Vladan; Lukin, Mikhail | We demonstrate photon-mediated interactions between two individually trapped atoms coupled to a nanophotonic cavity. | |

400 | Generating multipartite entangled states with Cavity Rydberg Polaritons | Alaeian, Hadiseh; Pfau, Tilman | In this work, I introduce a new type of quasi-particles called cavity-Rydberg polariton, with large interaction inherited from their strongly-interacting Rydberg constituents. | |

401 | Parity switching in a semiconductor-based transmon qubit | Sabonis, Deividas; Erlandsson, Oscar; Kringhøj, Anders; Van Heck, Bernard; Larsen, Thorvald; Karzig, Torsten; Pikulin, Dmitry; Krogstrup, Peter; Petersson, Karl; Marcus, Charles | We study charge parity switching in a superconductor-semiconductor nanowire-based transmon device that shows Little-Parks oscillations of its frequency as a function of magnetic field. | |

402 | Suppression of charge dispersion by resonant tunneling in a single-channel transmon qubit | Kringhøj, Anders; Van Heck, Bernard; Larsen, Thorvald; Erlandsson, Oscar; Sabonis, Deividas; Krogstrup, Peter; Casparis, Lucas; Petersson, Karl; Marcus, Charles | When approaching the pinch-off regime of the nanowire junction, we observe resonant behavior of the plasma frequency, which we attribute to the formation of a quantum dot in the junction. | |

403 | Efficient microwave measurement of superconducting optomechanical circuits | Peterson, Gabriel; Kotler, Shlomi; Lecocq, Florent; Cicak, Katarina; Jin, X. Y.; Simmonds, Raymond; Aumentado, Jose; Teufel, John | Here I report recent progress to increase microwave measurement efficiencies to enable new regimes of ponderomotive squeezing and displacement sensing beyond the standard quantum limit. | |

404 | A Scalable Nanophotonic Platform for Rare Earth Ions | Dutta, Subhojit; Goldschmidt, Elizabeth; Barik, Sabyasachi; Saha, Uday; Waks, Edo | We present a new nanophotonic platform with Thulium ions doped in single crystal Lithium niobate thin films on insulator, that supports scalable top down fabrication. | |

405 | Spin-photon interfaces based on tin-vacancy centers in diamond | Trusheim, Matthew; De Santis, Lorenzo; Chen, Kevin; Ciccarino, Christopher; Englund, Dirk; Narang, Prineha | Here we discuss theoretical and experimental work towards coherent spin-photon interfaces based on SnV centers at liquid-helium temperatures. | |

406 | Investigating Microwave Raman Transitions Beyond the Rotating Wave Approximation in the Electronic Ground State of the Nitrogen-Vacancy Center | Böhm, Florian; Nikolay, Niko; Neinert, Sascha; Sontheimer, Bernd; Benson, Oliver | We will present the implementation of a spin-forbidden coherent population swapping between the m s = -1 and m s = +1 states, without undergoing the spin allowed transition into the m s = 0 state via microwave Raman transitions and compare our experimental results with theoretical calculations. | |

407 | Solid-state defect based quantum modules | Hanks, Michael; Trupke, Michael; Munro, William; Nemoto, Kae | In this presentation, we compare and contrast a number of different solid-state defects – including the nitrogen-, silicon-, and germanium-vacancy centers in diamond, as well as a variety of defects in silicon carbide – according to their suitability for quantum modules based on strong coupling to optical cavities. | |

408 | Rolf Landauer and Charles H. Bennett Award in Quantum Computing talk | Brandão, Fernando | Rolf Landauer and Charles H. Bennett Award in Quantum Computing talk | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

409 | Resource theory of asymmetric distinguishability | Wang, Xin; Wilde, Mark | We introduce bits of asymmetric distinguishability as the basic currency in this resource theory, and we prove that it is a reversible resource theory in the asymptotic limit, with the quantum relative entropy being the fundamental rate of resource interconversion. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

410 | Quantifying non-Markovianity: a quantum resource-theoretic approach | Anand, Namit; Brun, Todd | We study quantum non-Markovianity as a resource theory and introduce the robustness of non-Markovianity: an operationally-motivated, optimization-free measure that quantifies the minimum amount of Markovian noise that can be mixed with a non-Markovian evolution before it becomes Markovian. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

411 | log singularities in studying quantum capacities | Siddhu, Vikesh | In this work, we present a new method for checking positivity and non-additivity of the one-shot quantum capacity. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

412 | Quuantum Simplicity: Complexity Science in a Quantum World | Gu, Mile | Here, I introduce computational mechanics, a branch of complexity science captures structure by building the simplest causal models of natural observations. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

413 | Coherence cost for measurement and computation under conservation laws | Tajima, Hiroyasu; Shiraishi, Naoto; Saito, Keiji; Nagaoka, Hiroshi | Here, we provide a solution to this open problem. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

414 | Fusion rules from entanglement | Shi, Bowen; Kato, Kohtaro; Kim, Isaac | We derive some of the axioms of the algebraic theory of anyon [A. Kitaev, Ann. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

415 | Nonequilibrium work relations of open quantum systems in one-time measurement scheme | Sone, Akira; Liu, Yi-Xiang; Cappellaro, Paola | To overcome this challenge, here we introduce well-defined notions of quantum heat and work in open quantum systems, based on the notion of guessed state defined by the one-time measurement scheme, as developed in [Phys. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

416 | An ergodic theorem for homogeneously distributed quantum channels with applications to matrix product states | Movassagh, Ramis; Schenker, Jeffrey | As an application, we describe the thermodynamic limit of ergodic Matrix Product States and derive a formula for the expectation value of a local observable and prove that the 2-point correlations of local observables in such states decay exponentially in the bulk with their distance. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

417 | Quantifying Structure and Information Processing in One-Dimensional Quantum Systems | Gier, David; Crutchfield, James | We develop a framework for studying one-dimensional quantum systems with stationary, ergodic dynamics and introduce quantum information properties related to the von Neumann entropies of blocks of qubits within a structured chain. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

418 | Measurement-Induced Randomness and Structure in Controlled Qubit Processes | Venegas-Li, Ariadna; Jurgens, Alexandra; Crutchfield, James | We present a model family of classically controlled qubit time series and show that measurement induces high complexity in these processes in two specific senses: they are inherently unpredictable (positive Shannon entropy rate) and they require an infinite number of features for optimal prediction (divergent statistical complexity). | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

419 | A study about complete cohering/decohering power with ancillary system. | Takahashi, Masaya; Streltsov, Alexander | In this talk we will discuss the cohering/decohering power of a quantum operation which quantifies the maximum amount of coherence which can be generated/eliminated through that operation taken over all input states. | Session 30: Landauer and Bennett Award Session: Quantum Resource Theories and Thermodynamics |

420 | Implementation of a multi-mode qubit in coaxial circuit QED: Part 1 | Sosnina, Sophia; Wills, James; Fasciati, Simone; Jebari, Salha; Campanaro, Giulio; Cao, Shuxiang; Spring, Peter; Tsunoda, Takahiro; Yang, Ian; Leek, Peter; Vlastakis, Brian | In this talk we introduce a simple multi-mode coaxial transmon qubit – a two-mode qubit with a dipole-like differential mode and a coaxial common mode. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

421 | Implementation of a multi-mode qubit in coaxial circuit QED: Part 2 | Wills, James; Sosnina, Sophia; Fasciati, Simone; Jebari, Salha; Campanaro, Giulio; Cao, Shuxiang; Spring, Peter; Tsunoda, Takahiro; Yang, Ian; Leek, Peter; Vlastakis, Brian | We discuss experimental results on a multi-mode qubit operating within a coaxial circuit QED architecture. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

422 | Chiral cavity quantum electrodynamics in a 3D microwave lattice coupled to a transmon qubit (Part 1) | Panetta, Margaret; Owens, Clai; Chakram, Srivatsan; Saxberg, Brendan; Roberts, Gabrielle; Ma, Ruichao; Simon, Jonathan; Schuster, David | Here we discuss the design and testing of this system and describe prospects for its application. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

423 | Chiral cavity quantum electrodynamics in a 3D microwave lattice coupled to a transmon qubit (Part 2) | Owens, Clai; Panetta, Margaret; Chakram, Srivatsan; Saxberg, Brendan; Roberts, Gabrielle; Simon, Jonathan; Schuster, David | We now describe our work combining a single transmon with this topological lattice, achieving, for the first time, a platform for chiral cavity quantum electrodynamics. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

424 | Driving a Dark State Qubit in 3D Waveguide QED | Zanner, Maximilian; Schneider, Christian; Juan, Mathieu; Gargiulo, Oscar; Oleschko, Stefan; Sharafiev, Aleksei; Kirchmair, Gerhard | We show experimentally that this two-qubit dark-state can be used as a qubit state even though it is embedded in an open system. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

425 | Universal control of superconducting cavities with weak nonlinearity | Eickbusch, Alec; Elder, Salvatore; Campagne-Ibarcq, Phillipe; Ding, Zhenghao; Jha, Shantanu; Frattini, Nicholas; Flühmann, Christa; Frunzio, Luigi; Schoelkopf, Robert; Devoret, Michel | In this talk, we extend the idea of using large displacements in a cavity’s phase space to perform universal control of a superconducting cavity with Kerr nonlinearity on the order of 1 Hz. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

426 | Entangling Bosonic Modes via an Engineered Exchange Interaction | Gao, Yvonne; Lester, Brian; Devoret, Michel; Frunzio, Luigi; Jiang, Liang; Girvin, Steven; Schoelkopf, Robert | Here, we develop an efficient circuit to implement this unitary and realize the operation in a three-dimensional circuit QED architecture. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

427 | The Kerr-cat qubit: efficient readout and two-qubit gates | Frattini, Nicholas; Grimm, Alexander; Puri, Shruti; Lei, Chan U; Mirrahimi, Mazyar; Devoret, Michel | In this talk, we review our implementation for the Kerr-cat qubit, which is based on the interplay between two-photon driving and Kerr nonlinearity. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

428 | Multiplexed photon number measurement of a cavity using the fluorescence of a coupled qubit. | Essig, Antoine; Ficheux, Quentin; Theau, Peronnin; Cottet, Nathanael; Lescanne, Raphael; Sarlette, Alain; Rouchon, Pierre; Leghtas, Zaki; Huard, Benjamin | In this contribution, we present a technique that avoids this constraint by using the resonant fluorescence of a qubit coupled to the resonator of interest and a multiplexing measurement of the fluorescence field. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

429 | Full characterization and universal control of a superconducting 3D transmon qudit | Wu, Xian; Martinez, Luis; Rosen, Yaniv; DuBois, Jonathan | Here, we use the lowest four levels of a 3D transmon as the quantum register, qudit, which is computational equivalent to two qubits. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

430 | Advancements in 3D cavity fabrication and design for improved multimode quantum memories | Oriani, Andrew; Chakram, Srivatsan; He, Kevin; Anferov, Alexander; Dixit, Akash; Owens, John; Schuster, David | In doing so we will present a pathway for developing these cavities into novel 3D multimode architectures for next-generation randomly accessible quantum memories and processors. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

431 | Towards strong multi-mode coupling between a transmon and a metamaterial resonator | Indrajeet, Sagar; Wang, Haozhi; Plourde, B.L.T.; LaHaye, Matthew; Hutchings, Matthew; Taketani, Bruno; Wilhelm, Frank | We discuss approaches to decrease the mode spacing in this system and simulate the spectrum numerically. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

432 | Observation of atom-photon bound states in a rectangular waveguide | Fedorov, Arkady; Nandakumar, Pradeepkumar; Rosario Hamann, Jose Andres; Zanner, Maximilian; Weides, Martin | Here, we report observation of an atom-photon bound state with a transmon qubit inserted in a three-dimensional rectangular waveguide. | Session 31: Multi-mode and 3D-Cavity Circuit QED Systems |

433 | Mediating interactions between superconducting microwave cavities with three-wave mixing, part 1 | de Graaf, Stijn; Chapman, Benjamin; Zhang, Yaxing; Mundhada, Shantanu; Koottandavida, Akshay; Frattini, Nicholas; Burkhart, Luke; Read, Alexander; Frunzio, Luigi; Girvin, Steven; Devoret, Michel; Schoelkopf, Robert | I will discuss experimental design considerations and the theory behind the coupled-cavity device. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

434 | Mediating interactions between superconducting microwave cavities with three-wave mixing, part 2 | Chapman, Benjamin; de Graaf, Stijn; Zhang, Yaxing; Mundhada, Shantanu; Koottandavida, Akshay; Frattini, Nicholas; Burkhart, Luke; Read, Alexander; Frunzio, Luigi; Girvin, Steven; Devoret, Michel; Schoelkopf, Robert | In this talk, we present preliminary measurements of two microwave cavities coupled by such a three-wave mixing element. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

435 | Superconducting radio frequency cavities with seconds of photon lifetime in quantum regime | Romanenko, Alexander; Pilipenko, Roman; Frolov, Daniil; Zorzetti, Silvia; Awida, Mohamed; Posen, Sam; Holland, Eric; Belomestnykh, Sergey; Grassellino, Anna | In this contribution we present the recent advancements [2] in the quantum regime performance of SRF cavities enabled by applying combined materials science investigations and vacuum heat treatments. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

436 | Exploiting tunable, ultrastrong nonlinearies of the cavity Cooper-pair transistor system for generating microwave quantum states | Braasch, William; Blencowe, Miles; Friedman, Oscar; Armour, Andrew; Brock, Benjamin; Rimberg, Alexander | We utilize the recently developed Wigner current vector field (Wigner current) construct to give a geometrical analysis of the formation and possible stabilization of quantum microwave oscillator states in the presence of dissipation and noise for the cCPT. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

437 | Passive Error Correction with Grid States in a Non-Reciprocal Superconducting Circuit | Rymarz, Martin; Bosco, Stefano; Ciani, Alessandro; DiVincenzo, David | Besides the incorporation of the gyrator into the theory of circuit quantum electrodynamics [2], we propose a non-reciprocal superconducting circuit comprising a gyrator, whose effective dynamics is described by the Hofstadter Hamiltonian [3]. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

438 | Cat-qubit operations preserving error structure | Gross, Jonathan; Puri, Shruti; Blais, Alexandre | We present additional operations fulfilling this requirement and discuss their potential for near- and long-term applications. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

439 | Multiplexed readout of four qubits in 3D cQED architecture using broadband JPA | Vijay, R | Multiplexed readout of four qubits in 3D cQED architecture using broadband JPA | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

440 | Waveguide Bandgap Engineering with an Array of Superconducting Qubits | Brehm, Jan; Stehli, Alexander; Poddubny, Alexander; Wolz, Tim; Rotzinger, Hannes; Ustinov, Alexey | In this work, we experimentally study an array of eight superconducting transmon qubits with local frequency control, which are all coupled to the mode continuum of a superconducting waveguide. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

441 | Quantum impurity simulation in a photonic crystal with superconducting circuits | Vrajitoarea, Andrei; Belyansky, Ron; Lundgren, Rex; Whitsitt, Seth; Gorshkov, Alexey; Houck, Andrew | Here, we apply this toolbox for exploring the physics of a quantum impurity coupled to a photonic crystal. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

442 | High coherence bosonic modes in long Josephson junction chains | Mehta, Nitish Jitendrakumar; Kuzmin, Roman; Grabon, Nicholas; Manucharyan, Vladimir | Here we present a way to get around the problem by using standing wave modes in 6mm long transmission line made out of two parallel chains of Josephson junctions[2]. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

443 | Experimental Realization of the bosonic Kitaev-Majorana model | Hung, Jimmy Shih-Chun; Busnaina, J.; Moghaddam, M.V.; Chang, Chung Wai; Vadiraj, Ananthapadmanabha; Wilson, C.M. | We present results for simulations on small lattices and discuss possibilities for scaling up the lattice size. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

444 | Driven quantum nonlinear resonators: new exact solution techniques and generalized photon blockade | Roberts, David; Clerk, Aashish | The effects we describe are well within the reach of current experiments in circuit QED, and could be harnessed for a variety of applications in quantum information processing. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

445 | Encoding qubits in Bloch states of superconducting devices | Stace, Thomas; Grimsmo, Arne; Mueller, Clemens; Cole, Jared; Thanh Le, Dat | We describe two related superconducting circuits, the transmon [1] and the dualmon [2] in terms of Bloch states that reflect periodic symmetries in their Hamiltonians. | Session 32: Multi-mode and 3D-cavity Circuit QED Systems |

446 | Noise-resilient quantum algorithm design for adiabatic quantum computers | Lin, Jian; Li, Xiaopeng | We have developed a novel architecture for automated design of quantum adiabatic algorithm by combining deep reinforcement learning and simulation annealing techniques. | Session 33: NISQ: Algorithms |

447 | Preserving symmetries in NISQ algorithms | Streif, Michael; Rieffel, Eleanor; Wang, Zhihui | In this talk, we show an analysis of the probability of staying in the correct subspace under the influence of realistic noise models. | Session 33: NISQ: Algorithms |

448 | Using Grover’s search algorithm to test a three-level quantum system | Geyko, Vasily; Castelli, Alessandro; Joseph, Ilon; Shi, Yuan; Graziani, Frank; Libby, Stephen; Parker, Jeffrey; Rosen, Yaniv; DuBois, Jonathan | In the present work, Grover’s search algorithm is modified and studied for application to a three-level “qutrit” quantum device. | Session 33: NISQ: Algorithms |

449 | Utilizing NISQ devices for evaluating quantum algorithms | Rieffel, Eleanor | We discuss opportunities and challenges for using NISQ devices to evaluate quantum algorithms, including in elucidating quantum computational mechanisms, in designing novel quantum algorithms, in compilation and error-mitigation, and in techniques for evaluating quantum algorithms empirically. | Session 33: NISQ: Algorithms |

450 | What we’ve learned from NISQ application experiments on Sycamore | Babbush, Ryan | In this talk, I will reflect on these questions in the context of Google’s recent application demonstration experiments on the Sycamore quantum processor. | Session 33: NISQ: Algorithms |

451 | Sequential minimal optimization for quantum-classical hybrid algorithms | Nakanishi, Ken; Fujii, Keisuke; Todo, Synge | We propose a sequential minimal optimization method for quantum-classical hybrid algorithms, which converges faster, is robust against statistical error, and is hyperparameter-free. | Session 33: NISQ: Algorithms |

452 | Systematically Improving Quantum Approximate Optimization Algorithm with an Adaptive Ansatz | Economou, Sophia; Zhu, Linghua; Tang, Ho Lun; Barron, George; Barnes, Edwin; Mayhall, Nicholas | Here we provide a solution by employing the recently introduced ADAPT-VQE 1 algorithm, an iterative approach to creating ansatze for VQEs. | Session 33: NISQ: Algorithms |

453 | Bounds on classical simulation of simple quantum models from quantum supremacy. | Love, Peter | We consider simple physically motivated quantum models that can display quantum supremacy and hence whose efficient simulation by classical means is unlikely. | Session 33: NISQ: Algorithms |

454 | Maximum weighted independent set and quantum alternating operator ansatz | Saleem, zain | We study the maximum weighted independent set problem of graph theory using the quantum alternating operator ansatz. | Session 33: NISQ: Algorithms |

455 | Multi-block ADMM Heuristics for Mixed-Binary Optimization on Classical and Quantum Computers | Gambella, Claudio; Simonetto, Andrea | We present a decomposition-based approach to extend the applicability of current approaches to mixed binary optimization (MBO) problems, so as to solve a broad class of real-world optimization problems. | Session 33: NISQ: Algorithms |

456 | Learning unitaries via gradient descent optimization | Kiani, Bobak; Maity, Reevu; Lloyd, Seth | In this work, we find that gradient descent requires at least d^2 parameters in an alternating operator sequence to learn an arbitrary unitary in U(d) with a desired accuracy. | Session 33: NISQ: Algorithms |

457 | Practical demonstration of quantum approximate optimization on Google’s superconducting qubit processor | Harrigan, Matthew | We demonstrate a practical implementation of QAOA on three problem families at various qubit counts and circuit depths. | Session 33: NISQ: Algorithms |

458 | Running large quantum circuits on small quantum computers | Le Régent, François-Marie; Ayral, Thomas; Saleem, Zain Hamid; Alexeev, Yuri; Suchara, Martin | In this work, we have implemented a recent theoretical proposal [1] consisting in splitting a large circuit into smaller fragments that can be run on smaller processors. | Session 33: NISQ: Algorithms |

459 | Reverse engineering a pairwise entanglement witness for a near-term N-qubit computer | Thompson, Nathan; Nguyen, Nam; Behrman, Elizabeth; Steck, James | Designing and implementing new and general algorithms for the noisy intermediate scale quantum (NISQ) computers that will soon be available is not easy. | Session 33: NISQ: Algorithms |

460 | Error-resilient Tensor Network-based Ansatz for a Noisy Quantum Computer | Baek, Unpil; Huggins, William; Whaley, Birgitta | To tackle this challenge, we integrate the geometric structure of Deep Multiscale Entanglement Renormalization Ansatz (DMERA) circuits with the low-cost verification of fermionic parity symmetry to simulate ground states of the Fermi-Hubbard model. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

461 | Machine learning of noise-resilient quantum circuits | Cincio, Lukasz; Coles, Patrick | In this work, we study how machine learning can be applied to formulate noise-aware circuit compilations that can be executed on near-term quantum hardware to produce reliable results. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

462 | Noise-Resilient Quantum Dynamics Using Symmetry-Preserving Ansatzes | Otten, Matthew; Cortes, Cristian; Gray, Stephen | We describe and demonstrate a method for the computation of quantum dynamics on small, noisy universal quantum computers. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

463 | Error Mitigation in Data Driven Circuit Learning | Hamilton, Kathleen; Kharazi, Tyler; Leyton-Ortega, Vicente; Pooser, Raphael | This talk focuses on the incorporation of matrix-based SPAM error mitigation into data-driven circuit learning for parameterized circuits implementing generative modeling tasks. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

464 | Preserving Symmetries for Variational Quantum Eigensolvers in the Presence of Noise | Barron, George; Gard, Bryan; Altman, Orien; Mayhall, Nicholas; Barnes, Edwin; Economou, Sophia | We show that encoding symmetries of the simulated Hamiltonian at the level of the ansatz used in the VQE provides improvements to both classical and quantum resources. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

465 | Querying quantum computers with neural networks: precise measurements and noise reduction | Mezzacapo, Antonio; Kandala, Abhinav; Mazzola, Guglielmo; Choo, Kenny Jing; Torlai, Giacomo; Carleo, Giuseppe | In this talk I will introduce neural-network estimators for quantum observables, obtained by integrating the measurement apparatus of a quantum simulator with neural networks. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

466 | Measurement Reduction in Variational Quantum Algorithms | Zhao, Andrew; Tranter, Andrew; Kirby, William; Ung, Shu Fay; Miyake, Akimasa; Love, Peter | We approach this problem from the perspective of contextuality, and use unitary partitioning to define VQE procedures in which additional unitary operations are appended to the ansatz preparation circuit to reduce the number of terms one needs to measure. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

467 | Noise Resilience of Variational Quantum Compiling | Sharma, Kunal; Khatri, Sumeet; Cerezo de la Roca, Marco; Coles, Patrick | In this work, we report on a surprising form of noise resilience for these algorithms. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

468 | Quantum Dynamical Complexity and Reliability of Analog Quantum Simulation | Chinni, Karthik; Poggi, Pablo; Deutsch, Ivan | We address these questions by studying the basic paradigms such as the ground state and the excited state quantum phase transitions in the Lipkin-Meshkov-Glick (LMG) model[1]. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

469 | Exploiting molecular point group symmetries for quantum simulation | Setia, Kanav; Whitfield, James; Mezzacapo, Antonio; Rice, Julia; Pistoia, Marco; Chen, Richard | In this work, we develop a formalism to reduce the number of qubits required for simulating molecules using spatial symmetries, by finding qubit representations of irreducible symmetry sectors. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

470 | Quantum-classical simulation of two-site dynamical mean-field theory on noisy quantum hardware | Keen, Trevor; Maier, Thomas; Johnston, Steven; Lougovski, Pavel | We report on a quantum-classical simulation of a two-site dynamical mean-field theory (DMFT) calculation. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

471 | Nearly Optimal Measurement Scheduling for Partial Tomography of Quantum States | Bonet-Monroig, Xavier; Babbush, Ryan; O’Brien, Thomas | In this work we design schemes for such parallelization with near-optimal complexity in the system size N. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

472 | Extracting state purity of a large system with limited control | Yanay, Yariv; Tahan, Charles | Here, we propose a method of extracting the purity with limited control, applied through multiplexed dispersive readout. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

473 | Evaluation of the classical sampling cost for noisy quantum circuits | Hakkaku, Shigeo; Fujii, Keisuke | In this work, we estimate the overhead for classical simulation of noisy quantum circuits in terms of Robustness of Magic (RoM) and stabilizer norm, and compare them. | Session 34: NISQ: Noise Resilience, Mitigation, and Characterization |

474 | Demonstration of a large-scale quantum chemistry calculations using the Sycamore quantum processor | Rubin, Nicholas; McClean, Jarrod; Jiang, Zhang; Harrigan, Matthew; Takeshita, Tyler; Babbush, Ryan | The model provides an efficiently verifiable circuit that has a large degree of entanglement and is a circuit primitive for broader fermionic simulation. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

475 | Energy gap calculation on near-term quantum hardware with robust phase estimation | Russo, Antonio; Baczewski, Andrew; Morrison, Benjamin; Rudinger, Kenneth | In particular, we calculate the energy landscapes of H 2 and H 3 on extant quantum hardware (pre-compiling to emulate hardware with significantly higher fidelities). | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

476 | Quantum simulation of molecular vibronic spectra on a superconducting bosonic processor: Part I | Curtis, Jacob; Wang, Christopher; Lester, Brian; Zhang, Yaxing; Gao, Yvonne; Freeze, Jessica; Batista, Victor; Vaccaro, Patrick; Chuang, Isaac; Frunzio, Luigi; Jiang, Liang; Girvin, Steven; Schoelkopf, Robert | Here, we a present a blueprint for realizing these capabilities in a superconducting architecture consisting of long-lifetime cavity modes coupled to transmon ancillae. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

477 | Quantum simulation of molecular vibronic spectra on a superconducting bosonic processor: Part II | Wang, Christopher; Curtis, Jacob; Lester, Brian; Zhang, Yaxing; Gao, Yvonne; Freeze, Jessica; Batista, Victor; Vaccaro, Patrick; Chuang, Isaac; Frunzio, Luigi; Jiang, Liang; Girvin, Steven; Schoelkopf, Robert | In this talk, we present a superconducting bosonic processor that combines high fidelity non-Gaussian state preparation, a complete set of Gaussian operations, and a novel single-shot photon number resolving measurement scheme. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

478 | Quantum computation of magnon spectra | FRANCIS, AKHIL; Freericks, James; Kemper, Alexander | We demonstrate quantum computation of two-point correlation functions for a Heisenberg spin chain. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

479 | Improving chemistry calculations with virtual quantum subspace expansion | Urbanek, Miroslav; De Jong, Wibe | This work explores practical viability of hybrid quantum-classical methods in quantum computing. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

480 | Accuracy of the effective Hamiltonian in the quantum simulation experiments | Mozgunov, Evgeny | For both approaches we provide an error estimate: the difference in the norm between the obtained effective Hamiltonian and the target. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

481 | Hybrid quantum-classical simulations of correlated materials within Gutzwiller variational approach | Yao, Yongxin; Berthusen, Noah; Zhang, Feng; Wang, Cai-Zhuang; Ho, Kai-Ming; Orth, Peter | We develop a hybrid quantum-classical simulation framework that leverages existing noisy intermediate-scale quantum (NISQ) computing technology to study ground-state properties of correlated electron materials. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

482 | Improvements in quantum algorithms for quantum chemistry and condensed matter | O’Brien, Thomas | In this talk, I will overview a number of recently developed algorithms and algorithmic improvements, and some experimental implementations thereof, including methods for state preparation, error mitigation, partial state tomography, and derivative estimation on a quantum device. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

483 | Quantum Chemistry as an application-insprired Benchmark on near-term quantum computers | Pooser, Raphael; Morris, Titus; McCaskey, Alexander; Jakowski, Jacek; Humble, Travis; Moore, Shirley | We will present results from application-inspired benchmarks, including Quantum Chemistry. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

484 | Quantum simulation of the dynamics of the Fermi-Hubbard model on Sycamore | Jiang, Zhang | Here, we report such an experiment on the dynamics of the Fermi-Hubbard model using Google’s Sycamore quantum chip. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

485 | Experimental realization of a nonlinear 3-wave mixing gate for quantum simulation | Castelli, Alessandro; Shi, Yuan; Joseph, Ilon; Geyko, Vasily; Graziani, Frank; Libby, Stephen; Parker, Jeffrey; Rosen, Yaniv; DuBois, Jonathan | We present a simulation of nonlinear 3-wave processes on a single qudit of the LLNL Quantum Design and Integration Testbed (QuDIT) resulting from iterative application of a gate developed to emulate these interactions. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

486 | Matrix product state simulations on a quantum computer | Feig, Michael; Potter, Andrew | We discuss near-term prospects for using small and non-error-corrected quantum computers to aid in MPS simulations. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

487 | Quantum simulation of nonlinear three-wave interactions with engineered cubic couplings | Shi, Yuan; Castelli, Alessandro; Joseph, Ilon; Geyko, Vasily; Graziani, Frank; Libby, Stephen; Parker, Jeffrey; Rosen, Yaniv; DuBois, Jonathan | In particular, for a three-wave Hamiltonian whose conserved actions are positive, we show that its Hilbert space can be decomposed into a direct sum of D-dimensional subspaces. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

488 | Simulating quantum systems on quantum computers | Fischer, Sean; Hellberg, C Stephen; Lanzagorta-Saldana, Marco; Gunlycke, Daniel | In this presentation, we discuss a new mapping method—called symmetry configuration mapping (SCM)—that uses the symmetry of the physical system to isolate different parts of the computational space. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

489 | Studying many-body localization on a universal quantum computer | Johri, Sonika; Zhu, Daiwei; Nguyen, Nhung; Alderete, Cinthia; landsman, kevin; Linke, Norbert; Monroe, Christopher; Matsuura, Anne | The study of this phenomena has been proposed as an application of near-term quantum computers. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

490 | Towards material design applications in a quantum computer | Barkoutsos, Panagiotis; Gkritsis, Fotios; Sokolov, Igor; Ollitrault, Pauline; Woerner, Stefan; Tavernelli, Ivano | In this talk we propose a quantum algorithm with favorable scaling in resource requirements, allowing for the solution of the material design problem in currently available noisy quantum processors. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

491 | Simulating quantum field theory in the light-front formulation | Kreshchuk, Michael; Kirby, William; Goldstein, Gary; Beauchemin, Pierre-Hugues; Love, Peter | As an example, we provide a detailed algorithm for calculating analogues of QCD parton distribution functions in a simple 1+1-dimensional model. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

492 | Simulating Dynamic Material Properties on Near-Term Quantum Computers | Bassman, Lindsay; Liu, Kuang; Geng, Yifan; Shebib, Daniel; Krishnamoorthy, Aravind; Fukushima, Shogo; Shimojo, Fuyuki; Kalia, Rajiv; Nakano, Aiichiro; Vashishta, Priya | In this work, we demonstrate successful simulation of time-dependent magnetization in a simplified model of an atomically-thin two-dimensional material on IBM’s Q16 Melbourne quantum processor and Rigetti’s Aspen quantum processor. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

493 | Robust Preparation of Many-body Ground States in Jaynes-Cummings Lattices | Cai, Kang; Parajuli, Prabin; Wong, Chee Wei; Long, Guilu; Tian, Lin | Here we study the robust preparation of the many-body ground states of polaritons in a finite-sized JC lattice by combining the techniques of quantum state engineering and adiabatic evolution. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

494 | Quantum Algorithm for Simulating a Driven Dissipative 3-site Hubbard Ring | Rost, Brian; Del Re, Lorenzo; Johnson, Michael; Kemper, Alexander; Freericks, James | We consider the simulation of a three site Hubbard model driven by an electric field, connected to a Fermionic bath. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

495 | Mapping Hamiltonians from material science onto near-term quantum devices | Tubman, Norm; O’Gorman, Bryan; Changlani, Hitesh | In this work we demonstrate that downfolding Hamiltonians, a process by which real materials are mapped on to model Hamiltonians, can yield a Hamiltonian form and size that is suitable for simulation on near-term quantum hardware. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

496 | Determining Hamiltonian eigenstates on a quantum computer using quantum imaginary time evolution | Motta, Mario; Sun, Chong; Tan, Adrian; O’Rourke, Matthew; Ye, Erika; Minnich, Austin; Brandão, Fernando; Chan, Garnet | We recently introduced [1] the quantum imaginary time evolution and quantum Lanczos algorithms, which are analogues of classical algorithms for finding ground and excited states. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

497 | Quantum Computation of the Ground and Excited State Energies Using Quantum Imaginary Time Evolution and Quantum Lanczos Methods | Yeter Aydeniz, Kubra; Pooser, Raphael; Siopsis, George | In this study, we demonstrate the application of these algorithms on a nontrivial quantum computation, using the deuteron binding energy as an example. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

498 | Driven-dissipative quantum mechanics on a lattice: Describing a fermionic reservoir with the master equation | Del Re, Lorenzo; Rost, Brian; Kemper, Alexander; Freericks, James | Here, I address a tight binding model of electrons driven out-of-equilibrium by an electric field, where the system can exchange energy and number of particles with a fermionic reservoir. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

499 | Quantum synchronization on the IBM Q system | Koppenhoefer, Martin; Bruder, Christoph; Roulet, Alexandre | We report the first experimental demonstration of quantum synchronization. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

500 | Quantum Digital Cooling | Polla, Stefano; Herasymenko, Yaroslav; O’Brien, Thomas | We introduce a new method for digital preparation of ground states of a simulated Hamiltonians, inspired by cooling in nature and adapted to leverage the capabilities of digital quantum hardware. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

501 | Resource-Efficient Quantum Algorithm for Protein Folding | Tavernelli, Ivano; Robert, Anton; Barkoutsos, Panagiotis; Woerner, Stefan | In this talk, I will present a folding algorithm that requires resources (number of qubits and gate operations) that scale polynomially with the number of amino acids (AA). | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

502 | Digital quantum simulation of quantum vibrational dynamics and control | Magann, Alicia; Grace, Matthew; Rabitz, Herschel; Sarovar, Mohan | In this talk, I will explore how digital quantum simulation could be used to make quantum optimal control simulations more tractable. | Session 35: NISQ: Quantum Chemistry and Quantum Simulation |

503 | Variational Quantum Fidelity Estimation | Cerezo de la Roca, Marco; Poremba, Alexander; Cincio, Lukasz; Coles, Patrick | We present an efficient, near-term algorithm for estimating the well-known fidelity, which quantifies the closeness of quantum states. | Session 36: NISQ: Variational Quantum Eigensolvers |

504 | Variational Quantum Algorithm for Markovian Open Quantum Systems | Yoshioka, Nobuyuki; Nakagawa, Yuya; Mitarai, Kosuke; Fujii, Keisuke | We propose a quantum-classical hybrid variational algorithm to simulate the non-equilibrium stationary states of Markovian open quantum systems, named the dissipative-system Variational Quantum Eigensolver (dVQE) [1]. | Session 36: NISQ: Variational Quantum Eigensolvers |

505 | Variational Generation of Thermofield Double States and Critical Ground States with a Quantum Computer | Matsuura, Anne; Johri, Sonika; Zhu, Daiwei; Linke, Norbert; landsman, kevin; Nguyen, Nhung; Alderete, Cinthia; Hsieh, Timothy; Monroe, Christopher | The entanglement structure of thermofield double and critical states plays a key role in the study of black holes, and our work simulates such nontrivial structures on a quantum computer. | Session 36: NISQ: Variational Quantum Eigensolvers |

506 | Exactly-solvable models as benchmarks for VQE | Robbins, Ken; Love, Peter | Exactly solvable models such as the Lipkin-Meshkov-Glick (LMG) model, a simple nuclear model of N fermions, can provide such benchmarks. | Session 36: NISQ: Variational Quantum Eigensolvers |

507 | Variational Quantum Linear Solver: A Hybrid Algorithm for Linear Systems | Bravo-Prieto, Carlos; LaRose, Ryan; Cerezo, Marco; Subasi, Yigit; Cincio, Lukasz; Coles, Patrick | In this work, we propose a variational hybrid quantum-classical algorithm for solving linear systems, with the aim of reducing the circuit depth and doing much of the computation classically. | Session 36: NISQ: Variational Quantum Eigensolvers |

508 | Variational Preparation of Quantum Hall States on a Lattice | Jones, Eric; Kapit, Eliot | Variational Preparation of Quantum Hall States on a Lattice | Session 36: NISQ: Variational Quantum Eigensolvers |

509 | Variational quantum simulation of the Fermi-Hubbard model | Choquette, Alexandre; Di Paolo, Agustin; Barkoutsos, Panagiotis; Senechal, David; Tavernelli, Ivano; Blais, Alexandre | In this talk, we propose a VQA to prepare the groundstate of the Fermi-Hubbard model. | Session 36: NISQ: Variational Quantum Eigensolvers |

510 | A Non-Orthogonal Variational Quantum Eigensolver | Huggins, William; Lee, Joonho; Baek, Unpil; O’Gorman, Bryan; Whaley, Birgitta | We present an extension to the variational quantum eigensolver that approximates the ground state of a system by solving a generalized eigenvalue problem in a subspace spanned by a collection of parametrized quantum states. | Session 36: NISQ: Variational Quantum Eigensolvers |

511 | Barren Plateau Issues for Variational Quantum-Classical Algorithms | Cerezo, Marco; Sone, Akira; Cincio, Lukasz; Coles, Patrick | Here, we rigorously prove two results related to the trainability of VQCAs. | Session 36: NISQ: Variational Quantum Eigensolvers |

512 | Approaching scalable VQE of interacting bosons with NISQ devices | Li, Andy C. Y.; Macridin, Alexandru; Spentzouris, Panagiotis | In this work, we discuss the appropriate VQE strategy suitable for multi-site interacting boson systems, for example, the Holstein model and the Rabi lattice model. | Session 36: NISQ: Variational Quantum Eigensolvers |

513 | Efficient Variational Generation of Thermofield Double States on a Superconducting Quantum Processor: Theory (Part 1) | Premaratne, Shavindra; Johri, Sonika; Zou, Xiang; Sagastizabal, Ramiro; Rol, Michiel Adriaan; Klaver, Berend; Moreira, Miguel; Almudever, Carmina; DiCarlo, Leonardo; Matsuura, Anne | We implement a quantum-classical hybrid variational optimization algorithm to efficiently generate TFD states of the tranverse-field Ising chain. | Session 36: NISQ: Variational Quantum Eigensolvers |

514 | Efficient Variational Generation of Thermofield Double States on a Superconducting Quantum Processor: Experiment (Part 2) | Sagastizabal, Ramiro; Rol, Michiel Adriaan; Klaver, Berend; Moreira, Miguel; Premaratne, Shavindra; Johri, Sonika; Zou, Xiang; Almudever, Carmina; Matsuura, Anne; DiCarlo, Leonardo | Specifically, we variationally approximate thermofield double (TFD) states through minimization of the constructed cost function described in Part 1. | Session 36: NISQ: Variational Quantum Eigensolvers |

515 | Efficient Symmetry-Preserving State Preparation Circuits for the Variational Quantum Eigensolver Algorithm | Zhu, Linghua; Gard, Bryan; Barron, George; Mayhall, Nicholas; Economou, Sophia; Barnes, Edwin | Here, we present efficient state preparation circuits that respect particle number, total spin, spin projection, and time-reversal symmetries. | Session 36: NISQ: Variational Quantum Eigensolvers |

516 | Noncontextuality as classicality in variational quantum eigensolvers | Kirby, William; Love, Peter | In this talk we show how to use contextuality, an indicator of non-classicality in quantum systems, to evaluate the variational quantum eigensolver (VQE), a promising tool for near-term quantum simulation. | Session 36: NISQ: Variational Quantum Eigensolvers |

517 | Shot Frugal Optimization for Variational Quantum-Classical Hybrid Algorithms | Arrasmith, Andrew; Kubler, Jonas; Cincio, Lukasz; Coles, Patrick | Specifically, we present new techniques and compare them with standard methods to demonstrate the potential for improvement both with noiseless and noisy quantum devices. | Session 36: NISQ: Variational Quantum Eigensolvers |

518 | Master equation approach to study Non-Markovian dynamics of open quantum systems | Chen, Yusui | Starting from stochastic Schrödinger equations, we demonstrate a systematical method to derive the exact time convolution-less master equation for various open quantum systems, e.g. qubit systems, multi-level systems, and harmonic oscillator systems. | Session 37: Open Quantum Systems |

519 | Markovian Entanglement Dynamics under Locally Scrambled Quantum Evolution | Kuo, Wei-Ting; Akhtar, Ahmed; Arovas, Daniel; You, Yizhuang | We introduce the entanglement feature formulation to concisely organize the entanglement entropies over all subsystems into a many-body wave function, which allows us to describe the entanglement dynamics using an imaginary-time Schrodinger equation, such that various tools developed in quantum many-body physics can be applied. | Session 37: Open Quantum Systems |

520 | Critical Properties of the Measurement-Induced Transition in Random Quantum Circuits | Zabalo, Aidan; Gullans, Michael; Wilson, Justin; Gopalakrishnan, Sarang; Huse, David; Pixley, Jed | We study the tripartite mutual information (TMI) as an alternative diagnostic of the transition that is finite at criticality while maintaining a volume law for p<p c and vanishing for p>p c. | Session 37: Open Quantum Systems |

521 | Boundary Theory of a Deformed AKLT Model on the Square Lattice | Martyn, John; Kato, Kohtaro; Lucia, Angelo | In this work, we present a method to calculate the boundary state of the 2D AKLT model in terms of a classical loop model, where loops, vertices, and crossings are each given a weight. | Session 37: Open Quantum Systems |

522 | Basic construction of a tensor network library | Baker, Thomas; Foley, Alexandre; Di Paolo, Agustin; Thompson, Martin | We present a template tensor network code written in the programming language julia. | Session 37: Open Quantum Systems |

523 | Tree tensor network study of out-of-time-order correlators on a sparse graph | White, Christopher; Swingle, Brian | In this talk I will describes a study of out-of-time-order correlators using tree tensor networks; I will also comment on some methodological subtleties. | Session 37: Open Quantum Systems |

524 | Sparsity of the stabilizer projector decomposition of a density matrix and robustness of magic | Huang, Yifei; Love, Peter | We extend the stabilizer rank of state vectors to mixed states and define the rank(minimal l_0 norm) for stabilizer projector decomposition of a density matrix and show its advantage over the rank of Pauli decomposition. | Session 37: Open Quantum Systems |

525 | Single T gate in a Clifford circuit drives transition to universal entanglement spectrum statistics | Zhou, Shiyu; Yang, Zhicheng; Hamma, Alioscia; Chamon, Claudio | In this paper we show, using finite-size scaling analysis of different measures of level spacing statistics, that in the thermodynamic limit, inserting a single T gate in the middle of a random Clifford circuit is sufficient to alter the entanglement spectrum from a Poisson to a Wigner-Dyson distribution. | Session 37: Open Quantum Systems |

526 | Recurrences in nonlinear few-body entanglement dynamics | Kiral, Alexander; Pattanayak, Arjendu | We study quantum tunneling for an initially pure coherent spin state in a many-body spin system. | Session 37: Open Quantum Systems |

527 | Entanglement spectrum and entropy in non-Hermitian systems | Chang, Po-Yao; You, Jhih-Shih; Wen, Xueda; Ryu, Shinsei | In this talk, we study both the entanglement spectrum and the entanglement entropy by use of a biothogonal basis in non-Hermitian free fermion systems. | Session 37: Open Quantum Systems |

528 | GPU-accelerated simulations of realistic quantum systems with a focus on Quantum Information and Computation. | Lasek, Aleksander; Lepage, Hugo; Barnes, Crispin; Arvidsson Shukur, David | In this talk we present our method of numerically simulating realistic quantum systems. | Session 37: Open Quantum Systems |

529 | Unified Quantum Parallel Computing Theory and Discrete Time Crystals | Wu, Cheng-Hsiao | Unified Quantum Parallel Computing Theory and Discrete Time Crystals | Session 37: Open Quantum Systems |

530 | Error rates in interacting Kitaev chains at finite temperature | Stenger, John; Mong, Roger; Pekker, David | We investigate how error rates depend on interactions and temperature using TEBD and perturbation theory. | Session 37: Open Quantum Systems |

531 | Time dependent variational principle with ancillary global Krylov subspace | Yang, Mingru; White, Steven | We present a method to represent the time-evolving state in a MPS with its bond dimension increased by state-averaging with global Krylov vectors. | Session 37: Open Quantum Systems |

532 | Variational quantum control for single- and two-qubit transmon gates | Ruiz Chamorro, Andres; Torrontegui, Erik; Garcia-Ripoll, Juan Jose | In this talk I will present a new set of techniques to design single-qubit and two-qubit gates for transmon qubits, which can be used to tune qubit frequencies, implement direct or cavity mediated CZ interactions [1], and √SWAP gates with tuneable couplers. | Session 38: Optimal Quantum Control |

533 | Universal gates for protected superconducting qubits using optimal control | Baker, Brian; Abdelhafez, Mohamed; Gyenis, Andras; Mundada, Pranav; Houck, Andrew; Schuster, David; Koch, Jens | In this talk I will discuss the use of quantum optimal control theory to realize quantum gates for two protected superconducting circuits: the heavy-fluxonium qubit and the 0-π qubit. | Session 38: Optimal Quantum Control |

534 | Uncomputability and complexity of quantum control | Bondar, Denys; Pechen, Alexander | To arrive at these results, we develop a technique based on establishing the equivalence between quantum control problems and Diophantine equations, which are polynomial equations with integer coefficients and integer unknowns. | Session 38: Optimal Quantum Control |

535 | Robust control for tight SWAP cold atom sensors | Hush, Michael; Pucincic, Viktor; Liebermann, Per; Carvalho, Andre; Slatyer, Harry; Chakravorty, Rajib; Ball, Harrison; Biercuk, Michael | We demonstrate that robust control techniques – related to dynamic decoupling and dynamically-corrected composite pulses – can significantly improve the sensitivity of cold atom sensors in tight SWAP conditions, achieving performance commensurate with state-of-the-art lab conditions. | Session 38: Optimal Quantum Control |

536 | Optimizing quantum circuits subject to cross coupling | Liebermann, Per; Ball, Harrison; Slatyer, Harry; Blok, Machiel; Ramasesh, Vinay; Carvalho, André; Pucincic, Viktor; Chakravorty, Rajib; Hush, Michael; Biercuk, Michael | We present a new optimization technique which creates time-optimized circuits capable of combating unwanted crosstalk in transmon circuits. | Session 38: Optimal Quantum Control |

537 | High fidelity unitary evolution using constrained control fields. | Figueiredo Roque, Thales; Clerk, Aashish; Ribeiro, Hugo | In this talk, we focus on presenting the general method and revisit the problem of single qubit gates in a transmon qubit. | Session 38: Optimal Quantum Control |

538 | Quantum optimal control in a ZZ-free qubit architecture | Shillito, Ross; Winik, Roni; Leroux, Catherine; Di Paolo, Agustin; Braumueller, Jochen; Kjaergaard, Morten; Vepsalainen, Antti; Kim, David; Yoder, Jonilyn; Gustavsson, Simon; Oliver, William; Blais, Alexandre | In this talk, we demonstrate the application of quantum optimal control in a newly proposed architecture in which the ZZ-interaction is inherently suppressed. | Session 38: Optimal Quantum Control |

539 | A comparative study for reinforcement learning and traditional algorithms on state transfer problem | Zhang, Xiaoming; Wang, Xin | We perform a comparative study on the efficacy of three RL algorithms: tabular Q-learning, deep Q-learning and policy gradient, as well as stochastic gradient descent and Krotov algorithms, in the problem of quantum state preparation. | Session 38: Optimal Quantum Control |

540 | A geometric approach to dynamically corrected gates | Barnes, Edwin | I will present recent progress in understanding and modeling the effects of noise on the dynamics of a qubit and show how this can be used to develop new ways to slow down decoherence. | Session 38: Optimal Quantum Control |

541 | Application of Pontryagin’s Minimum Principle to Grover’s Quantum Search Problem | Lin, Chungwei | In this work, Grover’s quantum search problem is mapped to a time-optimal control problem. | Session 38: Optimal Quantum Control |

542 | Variational quantum gate optimization on superconducting qubit system | Kentaro, Heya; Suzuki, Yasunari; Takeda, Yutaka; Singh, Akhil; Kono, Shingo; Nittoh, Koh-ichi; Kusuyama, Koichi; Tamate, Shuhei; Tabuchi, Yutaka; Fujii, Keisuke; Nakamura, Yasunobu | In this presentation, we propose a gate optimization method, where high-fidelity multi-qubit gates are generated by optimizing parametrized quantum circuits consisting of tunable high-fidelity single-qubit gates and fixed multi-qubit gates with limited controllability. | Session 38: Optimal Quantum Control |

543 | Using Algebra to Dissect Quantum Optical Evolution for Quantum Control | Martell, Riley; Van Huele, Jean-Francois; Beus, Ty; Berrondo, Manuel | Using Algebra to Dissect Quantum Optical Evolution for Quantum Control | Session 38: Optimal Quantum Control |

544 | Extending Modern C++ for Heterogeneous Quantum-Classical Computing | McCaskey, Alexander; Dumitrescu, Eugen; Lougovski, Pavel; Powers, Sarah; Moore, Shirley; Mintz, Tiffany | We present QCOR, a C++ language extension specification with an associated compiler that enables the programming of quantum expressions alongside standard C++ in a single-source context. | Session 39: Programming and Compiling: the QC Stack session |

545 | OpenPulse: Software for Experimental Physicists in Quantum Computing | Capelluto, Lauren; Alexander, Thomas | We introduce OpenPulse, a pulse-level programming component of Qiskit, that hands over analog control of quantum computing systems to the user. | Session 39: Programming and Compiling: the QC Stack session |

546 | qupulse: A quantum computing pulse parametrization and sequencing framework | Cerfontaine, Pascal; Humpohl, Simon; Prediger, Lukas; Bethke, Patrick; Kammerloher, Eugen; Schreiber, Lars; Meyer, Stefanie; Rumpe, Bernhard; Bluhm, Hendrik | We present an open source python package for the operation of advanced qubit control experiments, which emerged from our experimental work on spin qubits. | Session 39: Programming and Compiling: the QC Stack session |

547 | Compiled Quantum Optimization Algorithms in NISQ Processors | Venturelli, Davide; Do, Minh; O’Gorman, Bryan; Wang, Zhihui; Rieffel, Eleanor; Frank, Jeremy; LaRose, Ryan; Gomez Gonzalez, Vanesa | We discuss resource estimation and synthesis optimization results related to compilation of a variety of structured variational algorithms. | Session 39: Programming and Compiling: the QC Stack session |

548 | Optimizing compiler for Fermion simulation circuits | Wang, Qingfeng; Nam, Yunseong; Monroe, Christopher | In this talk, I will present a methodology that may be used to optimize these simulation circuits, leveraging the vastly large space from which a suitable mapping may be drawn. | Session 39: Programming and Compiling: the QC Stack session |

549 | Heuristics for Quantum Compiling with a Continuous Gate Set | Davis, Marc; Iancu, Costin | Abstract We present an algorithm for compiling arbitrary unitaries into a sequence of gates native to a quantum processor. | Session 39: Programming and Compiling: the QC Stack session |

550 | Introducing Control Flow in Qubit Allocation for Quantum Turing Machines | Cubeddu, Michael; Finigan, Will; Narang, Prineha; Vinokour, Vitali | In this work, we introduce a framework to reconcile the non-deterministic properties of quantum control flow when allocating virtual qubits from a given quantum circuit to physical qubits on a specific NISQ device in the pre-processing and compiling stage. | Session 39: Programming and Compiling: the QC Stack session |

551 | Noise-Aware Qubit Allocation Techniques for NISQ Devices | Cubeddu, Michael; Finigan, Will; Vinokour, Vitali; Narang, Prineha | We present our work in pre-processing error mitigation through variation-aware qubit allocation techniques for gate-based quantum computers, with a focus on superconducting platforms. | Session 39: Programming and Compiling: the QC Stack session |

552 | Benchmarking NISQ Devices Using qFlex | Mandra, Salvatore; Villalonga, Benjamin; Liakh, Dmitry; Boixo, Sergio | In my talk I will present qFlex, a fast and flexible software to simulate large RQCs to both verify and benchmark NISQ devices. | Session 39: Programming and Compiling: the QC Stack session |

553 | Characterization of State-dependent Noise in NISQ Processors | Sadlier, Ronald; Humble, Travis | We develop a method for characterizing state-dependent errors based on classical truth tables for the gate operations, and we use these results to compute the amplitudes of the corresponding channel operators. | Session 39: Programming and Compiling: the QC Stack session |

554 | Strategies for reducing the number of controlled gates on noisy intermediate scale quantum circuits | Mitarai, Kosuke; Fujii, Keisuke | We show that certain kind of controlled gates can be decomposed into a sequence of single-qubit operations when expectation values of some operators are needed. | Session 39: Programming and Compiling: the QC Stack session |

555 | qubit-ADAPT-VQE: An adaptive algorithm for constructing hardware-efficient ansätze on a quantum processor | Tang, Ho Lun; Grimsley, Harper; Mayhall, Nicholas; Barnes, Edwin; Economou, Sophia | Here, we present a hardware-efficient variant of this algorithm called qubit-ADAPT. | Session 39: Programming and Compiling: the QC Stack session |

556 | Sensitive and fast bolometer integrable with superconducting qubit readout | Mottonen, Mikko; Kokkoniemi, Roope; Girard, Jean-Philippe; Hazra, Dibyendu; Laitinen, Antti; Govenius, Joonas; Lake, Russell; Sallinen, Iiro; Vesterinen, Visa; Visakorpi, Eemil; Arpiainen, Sanna; Prunnila, Mika; Hakonen, Pertti | We report on a new type of a bolometer that simultaneously reaches the lowest noise reported for any bolometer, 20 zW/Hz 0.5 [1], and is roughly three orders of magnitude faster than the previous ultralow-noise bolometers. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

557 | Towards a Microwave Single Photon Detector Using Inelastic Cooper Pair Tunneling | Griesmar, Joël; Albert, Romain; Leppäkangas, Juha; Hofheinz, Max | We present here a photo-multiplier using the energy of a Cooper pair tunneling across a voltage-biased Josephson junction to convert one microwave photon into several photons at a different frequency. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

558 | Josephson single infrared photon detector | Walsh, Evan; Lee, Gil-Ho; Jung, Woochan; Huang, K.-F.; Wu, Bae-Ian; Efetov, Dmitri; Ohki, Thomas; Kim, Philip; Englund, Dirk; Fong, Kin Chung | In this talk, we report the experimental detection of near-infrared (NIR) single photons by a graphene-based JJ via non-resonant Cooper-pair breaking and the resulting quasiparticle diffusion. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

559 | Frequency tunable single microwave photodetector based on irreversible qubit-photon coupling | Albertinale, Emanuele; Lescanne, Raphaël; Déleglise, Samuel; Leghtas, Zaki; Esteve, Daniel; Bertet, Patrice; Flurin, Emmanuel | We report the observation of a new type of interaction between a two level system and a microwave resonator. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

560 | A Superconducting Detector That Counts Microwave Photons up to Two | Sokolov, Andrii; Wilhelm, Frank | We propose a detector of microwave photons which can distinguish the vacuum state, one-photon state, and the states with two or more photons. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

561 | Primary thermometry of propagating microwaves in the quantum regime | Scigliuzzo, Marco; Bengtsson, Andreas; Besse, Jean-Claude; Wallraff, Andreas; Delsing, Per; Gasparinetti, Simone | Here we propose and experimentally demonstrate primary thermometry of propagating microwave modes, using a transmon-type superconducting circuit. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

562 | Using Superconducting Qubits for Axion Dark Matter Detection | Dixit, Akash; Chakram, Srivatsan; Agrawal, Ankur; Naik, Ravi; Schuster, David; Chou, Aaron | Using Superconducting Qubits for Axion Dark Matter Detection | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

563 | High-Q Photonic Bandgap Microwave Cavity for Dark Matter Axion Searches | Agrawal, Ankur; Dixit, Akash; Yao, Wenjie; Johnson, Steven; Awida, Mohamed; Schuster, David; Chou, Aaron | We present various designs and experimental results of dielectric materials which can significantly increase the sensitivity and scanning rate of axion search. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

564 | Her Dark Materials: Comparison of Semiconducting Targets for Multi-Channel Direct Detection of Light Dark Matter | Inzani, Katherine; Trickle, Tanner; Zhang, Zhengkang; Zurek, Kathryn; Griffin, Sinéad | 1 The model takes into account three complementary interactions: nuclear recoils, electron transitions across band gaps and single phonon excitations. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

565 | Interfacial effects on phonon propagation through quantum sensors used for dark matter detection | Harrelson, Thomas; Griffin, Sinead | We use density functional theory simulations to describe the probability at which phonon distributions are transmitted through the target/TES interface, and the coherence losses in quasiparticle transmission to the sensor. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

566 | Gain calibration of a cryogenic amplification chain using normal-metal–insulator–superconductor junctions | Jenei, Máté; Hyyppä, Eric; Masuda, Shumpei; Tan, Kuan; Sevriuk, Vasilii; Silveri, Matti; Goetz, Jan; Partanen, Matti; Lake, Russell; Grönberg, Leif; Mottonen, Mikko | We present a gain calibration scheme [1] that utilizes a normal-metal –insulator–superconductor junction, which is capacitively coupled to a superconducting microwave resonator [2]. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

567 | Josephson Parametric Amplifiers Fabricated in Wafer-scale with Side-wall Passivated Spacer Junction Technology | Vesterinen, Visa; Simbierowicz, Slawomir; Grönberg, Leif; Lehtinen, Janne; Najafi Jabdaraghi, Robab; Prunnila, Mika; Govenius, Joonas | We present our latest experimental results on Josephson parametric amplifiers (JPAs) fabricated with our Nb/Al-AlO x/Nb junction process. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

568 | Noise performance of a three-wave mixing kinetic inductance traveling-wave parametric amplifier | Malnou, Maxime; Gao, Jiansong; Vissers, Michael; Ullom, Joel | Here, we present a KIT based on a sub-micron resolution structure that is biased with a dc current and pumped in a three-wave mixing fashion. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

569 | Overlap junction-based Josephson parametric amplifiers (O-JPA) | Bal, Mustafa; Long, Junling; Zhao, Ruichen; Wang, Haozhi; McRae, Corey Rae; Lake, Russell; Park, Sungoh; Wu, Xian; Ku, Hsiang-Sheng; Frolov, Daniil; Pilipenko, Roman; Zorzetti, Silvia; Holland, Eric; Romanenko, Alexander; Pappas, David | We present the fabrication details as well as the characterization of O-JPAs. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

570 | Fabrication tolerances for traveling wave parametric amplifiers | Feng, Dennis; Vahidpour, Mehrnoosh; Mohan, Yuvraj; Stanwyck, Sam; Whyland, Tyler; Sharac, Nicholas; Ramachandran, Ganesh; Selvanayagam, Michael | We develop a method to analyze the performance of the TWPA with emulated fabrication variations and different process parameters. | Session 40: Quantum Amplifiers, Bolometers, and Detectors |

571 | Toward integration of Kerr-nonlinear parametric oscillators for adiabatic quantum computation with Lechner-Hauke-Zoller scheme | Kanao, Taro; Goto, Hayato | In this study, we investigate LHZ-scheme KPO networks with larger number of KPOs. | Session 41: Quantum Annealing and Optimization |

572 | Long range coupling through a chain of RF-SQUIDs for superconducting flux qubit quantum annealers | Martinez, Antonio; Tennant, Daniel; Dai, Xi; Melanson, Denis; Yurtalan, Ali; Bedkihal, Salil; Tang, Edward; Melville, Alexander; Niedzielski, Bethany; Das, Rabindra; Kim, David; Yoder, Jonilyn; Weber, Steven; Kerman, Andrew; Novikov, Sergey; Disseler, Steven; Basham, James; Grover, Jeffrey; Mozgunov, Evgeny; Lidar, Daniel; Lupascu, Adrian | We report on a subgraph of the coupler tree consisting of 2 capacitively shunted flux qubits connected by 7 RF-SQUIDs. | Session 41: Quantum Annealing and Optimization |

573 | Finding optimized anneal paths in capacitively shunted flux qubits | Khezri, Mostafa; Grover, Jeffery; Lidar, Daniel | In this work we study a capacitively shunted flux qubit (CSFQ), and use spectroscopy and dispersive readout to extract system parameters and model the qubit. | Session 41: Quantum Annealing and Optimization |

574 | Quantum annealing with spin lock technique | Hakoshima, Hideaki; Matsuzaki, Yuichiro; Seki, Yuya; Kawabata, Shiro | Here, we propose an alternative way to implement a spin-lock based QA, which effectively tunes the qubit frequency by a continuous drive. | Session 41: Quantum Annealing and Optimization |

575 | Assessing the potential of Rydberg atoms for adiabatic quantum computing of an NP-hard problem | Marchand, Bertrand; Serret, Fabrice; Ayral, Thomas | We present numerical estimates of the approximation ratio achieved by this approach under realistic noise conditions, on a class of experimentally-implementable random graphs. | Session 41: Quantum Annealing and Optimization |

576 | A theoretical analysis of the power of pausing | Chen, Huo; Lidar, Daniel | In this work, we present a theoretical analysis that explains these observations. | Session 41: Quantum Annealing and Optimization |

577 | Quantum computation using Kerr-nonlinear parametric oscillators | Goto, Hayato | Here we review the QbM with its recent progress. | Session 41: Quantum Annealing and Optimization |

578 | Effectiveness of quantum annealing pause and partial gauges on embedded degree-bounded minimum spanning tree problems | Grabbe, Shon; Gonzalez Izquierdo, Zoe; Hadfield, Stuart; Marshall, Jeffrey; Wang, Zhihui; Rieffel, Eleanor; Cramer, Nicholas | To support experimentation on early hardware, we consider as a surrogate problem finding the minimum degree-bounded spanning tree within a communication graph. | Session 41: Quantum Annealing and Optimization |

579 | Quantum annealing with boundary canceling schedules | Munoz-Bauza, Humberto; Campos Venuti, Lorenzo; Lidar, Daniel | Quantum annealing with boundary canceling schedules | Session 41: Quantum Annealing and Optimization |

580 | The Perils of Embedding for Sampling Problems | Marshall, Jeffrey; Di Gioacchino, Andrea; Rieffel, Eleanor | We observe that the simplest projection technique, majority vote, can fail quite spectacularly at preserving distribution properties. | Session 41: Quantum Annealing and Optimization |

581 | Reproducing the Performance Enhancement of Adiabatic Reverse Annealing | Kowalsky, Matthew; Albash, Tameem | We propose a conventional (forward) quantum annealing protocol with a diagonal catalyst of programmable strength λ. | Session 41: Quantum Annealing and Optimization |

582 | Reverse quantum annealing with dissipation | Passarelli, Gianluca; Yip, Ka Wa; Lucignano, Procolo; Lidar, Daniel; Nishimori, Hidetoshi | Here we investigate the performance of reverse annealing for the p-spin model in a low-temperature open system setting. | Session 41: Quantum Annealing and Optimization |

583 | Quantum annealing in a degenerate two-level system | Watabe, Shohei; Seki, Yuya; Kawabata, Shiro | In this presentation, we show that a degenerate two-level system that is called quantum Wajnflasz-Pick model may provide the higher success probability than the conventional spin-1/2 model in a weak longitudinal magnetic field region. | Session 41: Quantum Annealing and Optimization |

584 | Adaptive measurement approach towards controlling non-adiabatic transitions in quantum annealing | Bedkihal, Salil; Canturk, Mehmet; Tang, Yongchao; Martinez, Antonio; Lupascu, Adrian; Zhang, Song; Atalaya, Juan; Whaley, Birgitta | In this work, we present an adaptive annealing protocol based on measurement of the energy-level curvature. | Session 41: Quantum Annealing and Optimization |

585 | Elucidating the interplay between non-stoquasticity and the sign problem | Gupta, Lalit; Hen, Itay | In this study, we make an attempt to elucidate the circumstances under which the sign problem emerges and to clear up some of the confusion surrounding this intricate computational phenomenon. | Session 41: Quantum Annealing and Optimization |

586 | All-optical Ising machine by spatial light modulation | Pierangeli, Davide; Marcucci, Giulia; Conti, Claudio | Here, we make use of optical spins that are encoded and controlled by spatial light modulation to realize a large-scale all-optical Ising machine [1]. | Session 41: Quantum Annealing and Optimization |

587 | Is Fault Welcoming Quantum Computing Realistic? | Kapit, Eliot; Oganesyan, Vadim | An error-corrected, fault tolerant quantum computer is one of the most important long term goals of quantum computing research. | Session 41: Quantum Annealing and Optimization |

588 | Schrieffer-Wolff Methods for Annealing Qubits | Magyar, Rudolph; Ferguson, David | Schrieffer-Wolff Methods for Annealing Qubits | Session 41: Quantum Annealing and Optimization |

589 | Beyond Standard Quantum Annealing | Albash, Tameem | We review recent work exploring new quantum annealing protocols, including adiabatic reverse annealing and the introduction of catalyst Hamiltonians. | Session 41: Quantum Annealing and Optimization |

590 | A real-time path integral representation of driven quantum algorithms | Wilhelm, Frank; Headley, David; Schuhmacher, Peter | We apply path integral techniques such as eikonals and semiclassics in order to provide a way to better understanding under which conditions we can expect these algorithms to reliably converge. | Session 41: Quantum Annealing and Optimization |

591 | Updates to Hybrid Quantum-Classical Annealing | Schuhmacher, Peter; Misra, Aditi; Bedkihal, Salil; Dai, Xi; Lupascu, Adrian; Wilhelm, Frank | In this work, we discuss different strategies to generalize HQCA to larger qubit numbers. | Session 41: Quantum Annealing and Optimization |

592 | Non-stoquastic interactions of superconducting circuits in the low frequency regime | Schöndorf, Marius; Wilhelm, Frank | For this we use different theoretical tools, e.g. renormalization group techniques. | Session 41: Quantum Annealing and Optimization |

593 | Oscillatory quantum optimization methods applied to problems with large ground state bands | Tang, Zhijie; Kapit, Eliot | We explore how accelerated thermalization in low energy bands can provide a potentially noise tolerant quantum speedup for optimization and machine learning. | Session 41: Quantum Annealing and Optimization |

594 | How Quantum is the Speedup in Adiabatic Unstructured Search? | Hen, Itay | I will discuss in the above context the sensitivity of the quantum adiabatic unstructured search algorithm [Roland and Cerf, Phys. | Session 41: Quantum Annealing and Optimization |

595 | On Constructing Driver Hamiltonians for Several Linear Constraints | Leipold, Hannes; Spedalieri, Federico | In this work, we develop an algebraic framework for reasoning about the commutation of Hamiltonians with linear constraints – one that allows us to classify the complexity of finding a driver Hamiltonian for a set of constraints as NP-Hard through a reduction to the Subset Equal Sums problem as well as design a simple algorithm to solve the problem for Hamiltonians with bounded number of higher body interaction terms. | Session 41: Quantum Annealing and Optimization |

596 | Generating Weighted MAX-2-SAT Instances with Tunable Frustration on an RBM | Pei, Yan Ru; Manukian, Haik; Di Ventra, Massimiliano | Here, we propose a method of generating weighted MAX-2-SAT instances inspired by the frustrated-loop algorithm used by the quantum annealing community to generate Ising instances on a cubic lattice with nearest-neighbor couplings. | Session 41: Quantum Annealing and Optimization |

597 | Projecting NISQ-era quantum advantage with QAOA | Guerreschi, Gian Giacomo; Larkin, Jason; Justice, Daniel | The results demonstrate the importance of algorithm and problem selection and we discuss the performance data in the context of projecting NISQ-era quantum advantage. | Session 41: Quantum Annealing and Optimization |

598 | Small-parameter and operator series approaches for quantum approximate optimization | Hadfield, Stuart; Hogg, Tad; Rieffel, Eleanor | We show a calculus for analyzing algorithms based on quantum alternating operator ansatze, in particular the quantum approximate optimization algorithm (QAOA). | Session 41: Quantum Annealing and Optimization |

599 | Reinforcement Learning for Finding QAOA Parameters | Alexeev, Yuri; Khairy, Sami; Shaydulin, Ruslan; Cincio, Lukasz; Balaprakash, Prasanna | We used reinforcement learning (RL) framework to learn a policy network to optimize QAOA circuits and a kernel density estimation (KDE) technique to learn a generative model of optimal QAOA parameters. | Session 41: Quantum Annealing and Optimization |

600 | Quantum approximate optimization of the exact-cover problem on a superconducting quantum processor | Bengtsson, Andreas; Vikstål, Pontus; Warren, Christopher; Svensson, Marika; Johansson, Göran; Delsing, Per; Ferrini, Giulia; Bylander, Jonas | Here, we use the quantum approximate optimization algorithm (QAOA) to solve small instances of the NP-complete exact-cover problem. | Session 41: Quantum Annealing and Optimization |

601 | QAOA for Optimal Flight Gate Assignment | Stollenwerk, Tobias; Hadfield, Stuart; Wang, Zhihui | In this work, we present a Quantum Alternating Operator Ansatz for the problem of optimal assignment of airplanes to gates in a large airport hub. | Session 41: Quantum Annealing and Optimization |

602 | Probing topological defect formation in a quantum annealer | Bando, Yuki; Gómez-Ruiz, Fernando J.; Ohzeki, Masayuki; Oshiyama, Hiroki; Shibata, Naokazu; Susa, Yuki; Suzuki, Sei; Lidar, Daniel; Del Campo, Adolfo; Nishimori, Hidetoshi | We argue that the distribution of the number of defects generally follows a Poisson binomial distribution with all cumulants exhibiting a universal power-law scaling with the quench rate. | Session 41: Quantum Annealing and Optimization |

603 | Simulations of the Ising Model on a Shastry-Sutherland Lattice by Quantum Annealing | Kairys, Paul; Boothby, Kelly; Ozfidan, Isil; Raymond, Jack; King, Andrew; Banerjee, Arnab; Humble, Travis | We present a novel embedding of the lattice into the D-Wave 2000Q processor and use forward and reverse annealing to compute the phase diagram and probe the magnetization plateaus in the classical limit of zero transverse field. | Session 41: Quantum Annealing and Optimization |

604 | Excited-state search by quantum annealing toward quantum chemistry calculations | Seki, Yuya; Matsuzaki, Yuichiro; Kawabata, Shiro | We propose two methods to obtain the excited states: methods using non-adiabatic transition and adiabatic transition. | Session 41: Quantum Annealing and Optimization |

605 | Isomer Search on the D-Wave Quantum Annealer | Mniszewski, Susan; Terry, Jason; Akrobotu, Prosper; Negre, Christian | This paper describes a procedure for determining all the structural isomers of alkanes. | Session 41: Quantum Annealing and Optimization |

606 | Exploring phase transitions in a quantum dimer using a quantum annealer | Pokharel, Bibek; Takada, Kabuki; Nishimori, Hidetoshi; Lidar, Daniel | We consider an archetypical problem that is classically trivial, but difficult for AQC: an Ising ladder exhibiting a first-order phase transition with an exponentially closing gap, and a second-order phase transition with a polynomially closing gap. | Session 41: Quantum Annealing and Optimization |

607 | Solving the Graph Isomorphism Problem on a Quantum Annealer | Gonzalez Izquierdo, Zoe; Hen, Itay; Zhou, Ruilin | Following the lead of previous work, we use a D-Wave quantum annealer to distinguish between pairs of graphs with the same classical Ising spectrum by gathering statistics on the energy and other observables. | Session 41: Quantum Annealing and Optimization |

608 | Optimizing annealing parameters using genetic algorithms | Stromswold, Samuel; Wudarski, Filip; Rieffel, Eleanor | We seek to bridge this gap by using genetic algorithms to select parameters. | Session 41: Quantum Annealing and Optimization |

609 | Quantum annealing applied to ionic diffusion analysis | Uchimura, Keishu; Ichibha, Tom; Nakano, Kousuke; Hongo, Kenta; Maezono, Ryo | We applied the quantum annealing framework to a problem of ionic diffusions in solids. | Session 41: Quantum Annealing and Optimization |

610 | Experimentally Testing Quantum Critical Dynamics Beyond the Kibble-Zurek Mechanism | Gomez-Ruiz, Fernando; Cui, Jin; Huang, Yun-Feng; Li, Chuan-Feng; Guo, Guang-Can; Del Campo, Adolfo | We experimentally verify the distribution of kink pairs resulting from driving a one-dimensional quantum Ising chain through the paramagnet-ferromagnet quantum phase transition, using a single trapped ion as a quantum simulator in momentum space. | Session 41: Quantum Annealing and Optimization |

611 | Quantum Simulations of Superconducting Flux Circuits | Halverson, Thomas; Gupta, Lalit; Goldstein, Moshe; Hen, Itay | Quantum Simulations of Superconducting Flux Circuits | Session 41: Quantum Annealing and Optimization |

612 | Towards fault-tolerant quantum error correction with spins in diamond | Abobeih, Mohamed; Randall, Joe; Wang, Yang; Loenen, Sjoerd; Bradley, Conor; Terhal, Barbara; Taminiau, Tim Hugo | Here, I will present our progress towards the implementation of a fault-tolerant QEC code using a solid-state spin register in diamond. | Session 42: Quantum Computing with Defects |

613 | Hardware-Efficient Quantum Error Correction with NV Center | Chen, Mo; Layden, David; Cappellaro, Paola | To reduce the overhead, a hardware-efficient QEC approach has recently been employed and enjoyed experimental success [1]. | Session 42: Quantum Computing with Defects |

614 | Detection and control of large systems of nuclear-spin qubits in diamond | Randall, Joe; Abobeih, Mohamed; Bradley, Conor; van der Gronden, Floris; Degen, Maarten; Bartling, Hans; Taminiau, Tim Hugo | Building on these recent results, I will present new methods that allow us to extend control over more nuclear spin qubits. | Session 42: Quantum Computing with Defects |

615 | Hidden Silicon-Vacancy Centers in Diamond | Smallwood, Christopher; Ulbricht, Ronald; Day, Matthew; Schroder, Tim; Bates, Kelsey; Autry, Travis; Diederich, Geoffrey; Bielejec, Edward; Siemens, Mark; Cundiff, Steven | Here we report measurements on a high-density sample of negatively charged SiV – centers in diamond through the use of collinear optical multidimensional coherent spectroscopy (MDCS). | Session 42: Quantum Computing with Defects |

616 | Second-order Nonlinear Frequency Conversion and Integrated Color Centers in Silicon Carbide Nanophotonics | Guidry, Melissa; Lukin, Daniil; Dory, Constantin; Yang, Kiyoul; Vasireddy, Praful; Nasr, Mamdouh; Nanni, Emilio; Vuckovic, Jelena | We introduce color centers into thin films via electron irradiation and study the optical stability of single defects. | Session 42: Quantum Computing with Defects |

617 | Controlling the Silicon Vacancy in Silicon Carbide via Electric and Magnetic Fields | Lukin, Daniil; Guidry, Melissa; Sun, Shuo; Dory, Constantin; Vuckovic, Jelena | We demonstrate the optical transitions of the Silicon Vacancy are widely tunable via electric fields, which may enable multi-emitter scalability. | Session 42: Quantum Computing with Defects |

618 | Computational identification of defect qubits in transition metal dichalcogenide WSe2 | Tsai, Jeng-Yuan; Pan, Jinbo; Yan, Qimin | Our computational studies focus on point defects in WSe 2 as one of the well-known compounds in the family of transition metal dichalcogenides (TMDs). | Session 42: Quantum Computing with Defects |

619 | Probing the Coherent Spin Dynamics of Divacancies in Silicon Carbide with Spin Correlated Low-Field Magnetoresistance | McMillan, Stephen; Flatté, Michael | We describe an approach we predict will allow exploration of the coherent spin dynamics of these divacancies through low-field magnetoresistance by addressing an individual divacancy with a spin-polarized scanning tunneling microscope (SP-STM) [4]. | Session 42: Quantum Computing with Defects |

620 | Site-controlled generation of tin-vacancy centers in diamond via shallow ion implantation and subsequent diamond growth | Rugar, Alison; Lu, Haiyu; Dory, Constantin; Sun, Shuo; McQuade, Patrick; Shen, Zhixun; Melosh, Nicholas; Vuckovic, Jelena | In this talk we present a novel method to generate site-controlled SnV- centers with clean, consistent bulk spectra. | Session 42: Quantum Computing with Defects |

621 | Integrated Photonic Circuit for Generation and Isolation of Single Photons from Quantum Dot Ensembles | McDonald, Corey; Autry, Travis; Mirin, Richard; Silverman, Kevin | We will demonstrate on-chip generation of single photons from a QD ensemble, using ring resonators to isolate the emission of single dots. | Session 42: Quantum Computing with Defects |

622 | Ab-inito and crystal-field calculations of defect properties of Er3+ in yttria | Sahin, Cuneyt; Zhong, Tian; Flatté, Michael | We study electronic, structural, and spin properties of trivalent erbium impurities in yttria. | Session 42: Quantum Computing with Defects |

623 | Simultaneous manipulation of multiple diamond color centers for multiplexed repeaters | Sutula, Madison; Choi, Hyeongrak; Chen, Kevin; Wan, Noel; Lu, Tsung-Ju; Englund, Dirk | In this talk, we will discuss recent experimental progress on multiplexed repeaters based on color centers in diamond, with a particular focus on the efficient fluorescence collection towards high-speed entanglement distribution.1. | Session 42: Quantum Computing with Defects |

624 | Atomic-scale control of tunneling in few-donor quantum dots | Wang, Xiqiao; Kashid, Ranjit; Wyrick, Jonathan; Namboodiri, Pradeep; Rigosi, Albert; Fei, Fan; Silver, richard | This presentation covers our results in atomic-scale control and characterization of tunneling in STM-patterned devices in the few-donor quantum dots regime. | Session 42: Quantum Computing with Defects |

625 | Seeking superconductivity with new, two-dimensional dopants super-saturated in silicon | Tang, Ke; Kim, Hyun Soo; Ramanayaka, Aruna; Hoenk, Michael; Nikzad, Shouleh; Jewell, April; Pomeroy, Joshua | Here we explore the possibility of superconductivity in similar material systems using both n-type (antimony) and p-type (aluminum) delta-doped layers. | Session 42: Quantum Computing with Defects |

626 | EPR spectroscopy of Er:CaWO4 at millikelvin temperatures | Rancic, Milos; Le Dantec, Marianne; Bertet, Patrice; Vion, Denis; Chaneliere, Thierry; Goldner, Philippe; Bertaina, Sylvain | Here we present results from our recent Electron-Paramagnetic-Resonance (EPR) studies of 0.005% Er:CaWO 4. | Session 42: Quantum Computing with Defects |

627 | Demonstration and benchmarking of electron and nuclear 2-qubit logic gates with implanted donors in silicon | Morello, Andrea | Here we present the realization of a 2-qubit CNOT gate between weakly J-coupled electron spins, deploying our proposal of using the nuclear spins to detune the individual qubit frequencies [2]. | Session 43: Quantum Computing with Donor Spins |

628 | Driven dynamics of an electron coupled to spin-3/2 nuclei in quantum dots | Vezvaee, Arian; Sharma, Girish; Economou, Sophia; Barnes, Edwin | In this work, we present a comprehensive theoretical framework of a driven electron spin coupled to a nuclear spin-3/2 bath based on a mean-field approach, and we use it to study the effects of higher nuclear spin on dynamic nuclear polarization. | Session 43: Quantum Computing with Donor Spins |

629 | Long-time noise characteristics of an isotopically-enriched silicon nuclear spin bath | Grace, Matthew; Witzel, Wayne | We present a quantitative study of nuclear spin dynamics for moderately-sized baths over a range of timescales. | Session 43: Quantum Computing with Donor Spins |

630 | A silicon quantum-dot-coupled nuclear spin qubit | Hensen, Bas; Huang, Wister; Yang, Chih-Hwan; Chan, Kok; Yoneda, Jun; Tanttu, Tuomo; Hudson, Fay; Laucht, Arne; Itoh, Kohei; Ladd, Thaddeus; Morello, Andrea; Dzurak, Andrew | In this presentation, we report that for electrons in silicon metal-oxide-semiconductor quantum dots the hyperfine interaction is sufficient to initialize, read-out and control single silicon-29 nuclear spins, yielding a combination of the long coherence times of nuclear spins with the flexibility and scalability of quantum dot systems. | Session 43: Quantum Computing with Donor Spins |

631 | Engineering electrical control of single donor flip-flop qubits for universal quantum computations | Fernández de Fuentes, Irene; Botzem, Tim; Savytskyy, Rostyslav; Tenberg, Stefanie; Schmitt, Vivien; Tosi, Guilherme; Hudson, Fay; Itoh, Kohei; Jamieson, David; Dzurak, Andrew; Morello, Andrea | Here we present the progress in developing a CMOS compatible nanostructure, designed to enable accurate electric control of the hyperfine interaction (for coherent driving), and tunability on the coupling to charge reservoirs (for state readout). | Session 43: Quantum Computing with Donor Spins |

632 | Coherent electrical control of a single high-spin nucleus in silicon | Johnson, Mark; Asaad, Serwan; Mourik, Vincent; Joecker, Benjamin; Baczewski, Andrew; Firgau, Hannes; Madzik, Mateusz; Schmitt, Vivien; Pla, Jarryd; Hudson, Fay; Itoh, Kohei; McCallum, Jeffrey; Dzurak, Andrew; Laucht, Arne; Morello, Andrea | We report the discovery of Nuclear Electric Resonance (NER) in a single 123 Sb donor, implanted in a silicon nanoelectronic device [1]. | Session 43: Quantum Computing with Donor Spins |

633 | Decoherence of Dipole Coupled Flip-Flop Qubits | Truong, John; Hu, Xuedong | We study in detail this effective coupling, especially the effect of charge noise on two-qubit gates utilizing this coupling. | Session 43: Quantum Computing with Donor Spins |

634 | Full configuration interaction simulations of exchange coupled donors in silicon in an effective mass theory framework | Joecker, Benjamin; Baczewski, Andrew; Gamble, John; Pla, Jarryd; Morello, Andrea | Here, we use a full configuration interaction method within an established multivalley effective mass theory framework [3] to model the two-electron wavefunction for different donor configurations. | Session 43: Quantum Computing with Donor Spins |

635 | Simultaneous Comparison of Coulomb Blockade Linewidths of P Donor-based and MOS-based Si Quantum Dots | Hong, Yanxue; Ramanayaka, Aruna; Stewart, Michael; Wang, Xiqiao; Kashid, Ranjit; Namboodiri, Pradeep; Silver, richard; Pomeroy, Joshua | To study the extrinsic systematic noise origins and the intrinsic lattice couplings, here we report on the comparison of T eff on two different quantum dot systems, P donor-based and MOS-based Si quantum dots simultaneously measured using the same measurement setup on the same platform. | Session 43: Quantum Computing with Donor Spins |

636 | Evaluating effective mass models of the phoshorous donor in silicon | Pendo, Luke; Hu, Xuedong | We propose a scheme to solve a class of effective mass models with high precision. | Session 43: Quantum Computing with Donor Spins |

637 | A two-qubit gate between phosphorus donor electrons in silicon | He, Yu; Gorman, Samuel; Keith, Daniel; Kranz, Ludwik; Keizer, Joris; Simmons, Michelle | Here we report a ~800 ps √SWAP gate between phosphorus donor electron spin qubits in silicon with independent ~94 % fidelity single shot spin read-out. | Session 43: Quantum Computing with Donor Spins |

638 | Donor-bound excitons in Cl doped ZnSe quantum wells | Karasahin, Aziz; Jansen, Marvin; Pawlis, Alexander; Waks, Edo | Here we investigate emission properties of donor bound excitons in Cl doped ZnSe/ZnMgSe quantum wells. | Session 43: Quantum Computing with Donor Spins |

639 | G-factor Anisotropy of a Single Electron in a GaAs Quantum Dot | Svab, Simon; Camenzind, Leon; Yu, Liuqi; Stano, Peter; Zimmerman, Jeramy; Gossard, Arthur; Loss, Daniel; Zumbuhl, Dominik | Here, we present experiments studying the effect of the strength and direction of in-plane magnetic fields on the spin structure of an electron in a gated GaAs quantum dot. | Session 43: Quantum Computing with Donor Spins |

640 | Simulated Randomized Benchmarking of Dynamically Corrected Cross-Resonance Gate | Colmenar, Ralph Kenneth; Kestner, Jason | To improve the feasibility of such sequences, we make use of the fact that arbitrary Z rotations can be implemented virtually and with negligible error. | Session 44: Quantum Control and Quantum Gates |

641 | Experimental protection of qubit coherence up to relaxation times by using an image drive | Bertaina, Sylvain; Vezin, Herve; Chiorescu, Irinel | We go beyond their specific case and demonstrate a new pulse protocol in a number of materials with different spin Hamiltonians and environments. | Session 44: Quantum Control and Quantum Gates |

642 | Complete quantum-state tomography with a local random field | Arenz, Christian; Betzholz, Ralf; Cai, Jianming | We report the reconstruction of a highly entangled state between the electron and nuclear spin with fidelity above 95%, by randomly driving and measuring the NV-center electron spin only. | Session 44: Quantum Control and Quantum Gates |

643 | High sensitivity spectral characterization of local microwave fields using two-photon absorption processes of a transmon qudit | Tomarken, Spencer; DuBois, Jonathan | We present a scheme for characterizing the spectral transfer function of a superconducting transmon qudit capacitively coupled to a 3D cavity resonator. | Session 44: Quantum Control and Quantum Gates |

644 | Implementation of the XY interaction family by calibration of a single pulse | Abrams, Deanna; Didier, Nicolas; Johnson, Blake; Da Silva, Marcus; Ryan, Colm | Here we implement the full family of XY entangling gates in a transmon-based superconducting qubit architecture using a composite pulse scheme that requires calibration of only a single gate and maintains constant gate time for all members of the family. | Session 44: Quantum Control and Quantum Gates |

645 | Selective number-dependent arbitrary Hamiltonian engineering for a cavity | Wang, Chiao-Hsuan; Lebreuilly, José; Noh, Kyungjoo; Girvin, Steven; Jiang, Liang | By choosing control driving detunings much larger than the driving strengths, we propose a general approach to engineering a selective number-dependent arbitrary Hamiltonian for the cavity. | Session 44: Quantum Control and Quantum Gates |

646 | Implementing robust Holonomic quantum gates using dynamical invariant | Li, Yingcheng; Wan, Yidun | In this work, we propose a general dynamical invariant for 1 qubit and 2 qubit that is restricted in logical space that enables holonomic quantum computing without inverse engineering. | Session 44: Quantum Control and Quantum Gates |

647 | Superconducting cavity QED: box modes for quantum control of qubits | Olsen, Raina; Rezaee, Mohammadreza; Cohen, Eliahu; Karimi, Ebrahim | We treat the problem of a superconducting qubit in a THz cavity by quantizing Maxwell’s equations, showing that the driven system is described by the linearized Hamiltonian of cavity optomechanical systems used for quantum transduction. | Session 44: Quantum Control and Quantum Gates |

648 | Adiabatic Quantum Control of Dissipative State Preparation | Doucet, Emery; Brown, Tristan; Kamal, Archana | In this talk I will describe a scheme for preparing Bell states which employs only parametric qubit-qubit and qubit-resonator couplings. | Session 44: Quantum Control and Quantum Gates |

649 | Investigating the speed limit of two-qubit entangling gates with superconducting qubits | Howard, Joel; Long, Junling; Bal, Mustafa; Zhao, Ruichen; Zhao, Tongyu; Pappas, David; Gong, Zhexuan; Singh, Meenakshi | We demonstrate such speed limit experimentally using two superconducting transmon qubits with an always-on capacitive coupling. | Session 44: Quantum Control and Quantum Gates |

650 | High fidelity quantum gates for NV center defect registers based on dynamical decoupling sequences | Dong, Wenzheng; Calderon, Fernando; Economou, Sophia | Here we show that more complex dynamical decoupling sequences improve the nuclear spin operations, i.e., gate fidelity, applicability range, and nuclear spin selectivity. | Session 44: Quantum Control and Quantum Gates |

651 | Time-optimal robust controls for Molmer-Sorensen gates in large ion chains | Carvalho, Andre; Edmunds, Claire; Ball, Harrison; Hush, Michael; Biercuk, Michael | In this talk, we present numerically optimized modulation protocols which enable the realization of pairwise MS interactions in long ion chains. | Session 44: Quantum Control and Quantum Gates |

652 | Probing the quantum nature of electronic transport by sub-nanosecond time-resolved measurements | Simoneau, Jean Olivier; Lupien, Christian; Reulet, Bertrand | [1] In this talk, we present ultrafast time-domain measurements of the noise emitted by a tunnel junction under DC and AC excitation. | Session 44: Quantum Control and Quantum Gates |

653 | Optimizing pulses with geometric parameters for dynamically-corrected single qubit gate | Deng, Xiuhao | We used geometric parametrization to solve for the constraints of the control pulses to implement dynamically-corrected single qubit gate for superconducting qubits. | Session 44: Quantum Control and Quantum Gates |

654 | Robust and optimal control for SC qubits, two-qubit gates, and circuits | Ball, Harrison; Liebermann, Per; Carvalho, André; Slatyer, Harry; Perunicic, Vicktor; Chakravorty, Rajib; Hush, Michael; Biercuk, Michael | In this talk we describe error modelling of dominant error channels in superconducting circuits relevant for parametrically-activated or cross-resonance gates. | Session 44: Quantum Control and Quantum Gates |

655 | Triangular color codes on trivalent graphs with flag qubits | Chamberland, Christopher; Kubica, Aleksander; Yoder, Theodore; Zhu, Guanyu | We show how information from flag qubits can be use with the Restriction Decoder to maintain the effective distance of the code. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

656 | A numerical error threshold for "colorful" quantum computing | Hanish, Josey; Turner, Skylar; Blanchard, Eoin; Davis, Noah; La Cour, Brian | In this paper, we numerically test 3D colorful quantum computing’s resilience to noise. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

657 | Reinforcement learning for toric code error correction | Granath, Mats; Eliasson, Mattias; Fitzek, David; Frisk Kockum, Anton | I will present a summary of our efforts to use deep reinforcement learning (DRL) for quantum error correction of the toric code. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

658 | Qubit surface codes from rotation systems acting on Majorana fermions | Sarkar, Rahul; Yoder, Theodore | We instantiate this set of objects with Majorana operators and define a Majorana code by associating stabilizers to vertices and faces of the graph embedding. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

659 | Considerations for incorporating small logical qubits in digital error correction codes | Rodriguez Perez, David; Kapit, Eliot | In this talk, we consider using small logical qubits such as the VSLQ as part of a broader measurement-based code, and explore potential advantages and challenges from such a hybrid approach. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

660 | Higher-order autonomous quantum error correction | Lebreuilly, Jose; Noh, Kyungjoo; Wang, Chiao-Hsuan; Girvin, Steven; Jiang, Liang | In this work, we investigate the higher-order case and identify Knill-Laflamme conditions which, if satisfied up to some order r, lead to the existence of an AutoQEC protocol providing protection against at most r consecutive errors. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

661 | Characterization and critical faults of leakage errors on the surface code | Brown, Natalie; Cross, Andrew; Brown, Kenneth | In this paper, we study the effects of data leakage and ancilla leakage separately. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

662 | Fault tolerance on near-term trapped-ion logical qubits with a neural-network decoder | Obando Vargas, David; Lopez, Yefry; Gutierrez, Mauricio | Our goal is to find the break-even point where the logical memory outperforms the physical one. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

663 | Implementing a Logical Qubit on a Trapped Ion Quantum Information Processor | Egan, Laird; Cetina, Marko; Goldman, Michael; Risinger, Andrew; Noel, Crystal; Zhu, Daiwei; Biswas, Debopriyo; Monroe, Christopher | In this talk, we report on the experimental progress made towards implementation of quantum error correction, including the encoding of the logical qubit and stabilizer readout. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

664 | Environment noise analysis and real-time decoupling feedback control for a Nitrogen-Vacancy center | Danageozian, Arshag; Miller, Nathaniel; Barge, Pratik; Bhusal, Narayan; Dowling, Jonathan | Given that a small percentage of the Carbon atoms in diamond are Carbon 13 isotopes, we consider how the collective nuclear spins of these atoms affect the nuclear spin state of the Nitrogen 15 atom of the NV center, which is used as our computational qubit. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

665 | Mediator assisted cooling in quantum annealing | Pino Garcia, Manuel; García-Ripoll, Juan José | We show a significant reduction of errors for an architecture of quantum annealing where bosonic modes mediate the interaction between qubits. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

666 | Combined continuous error suppression and error correction for quantum annealing | Atalaya, Juan; Whaley, Birgitta; Niu, Murphy | Here we address the question of whether continuous error correction can enhance the performance of quantum annealing by further correcting the remaining unsuppressed errors. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

667 | Continuous error correction for evolution under time-dependent Hamiltonians | Zhang, Song; Atalaya, Juan; Niu, Murphy Yuezhen; Babakhani, Arman; Epstein, Jeffrey; Chan, Herman; Whaley, Birgitta | We analyze the continuous operation of a three-qubit code designed to protect the coherent evolution in the code space due to an encoded Hamiltonian. | Session 45: Quantum Error Correction Experiment and Theory (DQI) – Codes and Decoders |

668 | Breakdown of phenomenological Lindblad master equations in the strong coupling regime | Taketani, Bruno; Torres, J. Mauricio; Betzholz, Ralf | In this talk we investigate the effects of such separate, phenomenological description in optomechanical and spin-boson systems, which are particularly pronounced in the strong coupling regime and compare the results with a more realistic microscopic derivation of the master equation. | Session 46: Quantum Foundations |

669 | Entanglement classifier in chemical reactions | Li, Junxu; Kais, Sabre | After we explain how to implement this inequality to classify entanglement in scattering experiments, we propose a specific chemical reaction to test the violation of this inequality. | Session 46: Quantum Foundations |

670 | Concurrence and Discord measurements in a Kitaev type 1D Spin chain | Vimal, Vimalesh | We present the study of concurrence and quantum discord in the ground state of 1D spins. | Session 46: Quantum Foundations |

671 | Triangle Nonlocality : genuine quantum nonlocality and quantum Finner inequality | Renou, Marc-Olivier; Beigi, Salman; Brunner, Nicolas; Gisin, Nicolas; Boreiri, Sadra; Wang, Yuyi; Bäumer, Elisa | This talk is based on the two letters arXiv:1905.04902 and arXiv:1901.08287 | Session 46: Quantum Foundations |

672 | Evolution of entanglement in collective excitations in linear atomic chains | Townsend, Emily; Bryant, Garnett; Sarkar, Abhikbrata | We examine the time evolution of entanglement following plasmonic excitation due to coupling between the atomic chain and dipole emitters. | Session 46: Quantum Foundations |

673 | Entanglement and impropriety | La Cour, Brian; Yudichak, Thomas | We describe a classical model of quantum entanglement corresponding to spontaneous parametric downconversion. | Session 46: Quantum Foundations |

674 | Tripartite information, scrambling, and the role of Hilbert space partitioning in quantum lattice models | Schnaack, Oskar; Bölter, Niklas; Paeckel, Sebastian; Manmana, Salvatore; Kehrein, Stefan; Schmitt, Markus | In this work we investigate the time evolution of tripartite information as a natural operator-independent measure of scrambling, which quantifies to which extent the initially localized information can only be recovered by global measurements. | Session 46: Quantum Foundations |

675 | Tsirelson Polytopes and Randomness Generation | Bierhorst, Peter; Zhang, Yanbao; Knill, Emanuel | We classify the extreme points of polytopes of probability distributions in the (2,2,2) Bell-CHSH setting that are induced by a single Tsirelson bound. | Session 46: Quantum Foundations |

676 | Experimental Certification of a Minimal Informationally Complete Positive Operator-Valued Measure in a Device-Independent Protocol | Smania, Massimiliano; Mironowicz, Piotr; Nawareg, Mohamed; Pawlowski, Marcin; Cabello, Adan; Bourennane, Mohamed | We report on an experiment with entangled photon pairs that certifies for the first time a MIC-POVM for qubits following a device-independent protocol. | Session 46: Quantum Foundations |

677 | Many-particle interference and entanglement controlled by undetected particles | Lahiri, Mayukh | We present a unique interferometric scheme that allows us to generate many-particle entangled states. | Session 46: Quantum Foundations |

678 | Quantum State Reduction: Generalized Bipartitions from Algebras of Observables | Kabernik, Oleg; Pollack, Jason; Singh, Ashmeet | We investigate the general problem of identifying how the quantum state reduces given a restriction on the observables where the appropriate state-reduction map can be defined via a generalized bipartition, which is associated with the structure of irreducible representations of the algebra generated by the restricted set of observables. | Session 46: Quantum Foundations |

679 | Optimality in Quantum Data Compression using Dynamical Entropy | Androulakis, George | In this joint work with Duncan Wright we study lossless compression of strings of pure quantum states of indeterminate-length quantum codes which were introduced by Schumacher and Westmoreland. | Session 46: Quantum Foundations |

680 | Experimental Test of Leggett’s Inequalities with Solid-State Spins | Huang, Xianzhi; Ouyang, Xiaolong; Zhang, Wengang; Wang, Xin; Zhang, Huili; Yu, Yefei; Deng, Dongling; Duan, Luming | Here, we report an experimental test of Leggett’s nonlocal model with solid-state spins in a diamond nitrogen-vacancy center. | Session 46: Quantum Foundations |

681 | Objectivity In Different Quantum Reference Frames | Le, Thao; Mironowicz, Piotr; Horodecki, Pawel | Quantum Darwinism and its frameworks describe objectivity of quantum systems via their information in the environment. | Session 46: Quantum Foundations |

682 | The Nakano-Nishijima-Gell-Mann Formula From Galois Fields | Tanda, Satoshi; Ohaga, Tomoo; Nakatsugawa, Keiji; Fujii, Toshiyuki; Matsuyama, Toyoki | Here, we reexamine previous model [2] using isospin I z. Consequently, instead of the NNG formula, we obtained the alternate formula Q = 2( n + I z), where Q is charge number and n is multi-valuedness in Galois field. | Session 46: Quantum Foundations |

683 | Quantum Fields from Quantum Cellular Automata? A No-Go Theorem and a Path Forward | Brun, Todd; Mlodinow, Leonard | We show that this can be done in one spatial dimension, with the QCA being naturally described in terms of creation and annihilation operators that create or destroy particle locally, evolve straightforwardly under the QCA unitary, and obey the usual anticommutation relations (ACR). | Session 46: Quantum Foundations |

684 | Quantum mechanics and the covariance of physical laws in quantum reference frames | Giacomini, Flaminia | In my talk, I will introduce a general method to quantise reference frame transformations, which generalises the usual reference frame transformation to a “superposition of coordinate transformations”. | Session 46: Quantum Foundations |

685 | Quantum Mechanics of a Single Photon and the question of its Localizability in Space | Babaei, Hassan; Mostafazadeh, Ali | We identify the Hamiltonian operator with the generator of time translations, construct momentum and helicity operators, and introduce a chirality (direction-of-time) operator. | Session 46: Quantum Foundations |

686 | Quantized Electromagnetic-Field Propagation in a General Non-Local and Non-Stationary Dispersive and Absorbing Medium | Jacobs, Verne | We develop dynamical descriptions for the propagation of quantized electromagnetic fields, in the presence of environmental interactions. | Session 46: Quantum Foundations |

687 | Probability arises from entropy in axiomatic information thermodynamics | Westmoreland, Michael | Probability arises from entropy in axiomatic information thermodynamics | Session 46: Quantum Foundations |

688 | Emergence of the Born rule in quantum optics | Williamson, Morgan; La Cour, Brian | We consider this problem within the context of quantum optics using only classical physics and the assumption of a quantum electrodynamic vacuum that is real rather than virtual. | Session 46: Quantum Foundations |

689 | Interaction-Free Energy Transfer | Waegell, Mordecai; Elouard, Cyril; Huard, Benjamin; Jordan, Andrew | We consider a quantum block in the ground state of a confining potential, a superposition of inside and outside one arm of the MZ. | Session 46: Quantum Foundations |

690 | Diffraction-based Interaction-Free Measurements | Rogers, Spencer; Aharonov, Yakir; Elouard, Cyril; Jordan, Andrew | We consider the problem of determining if a single-slit contains a bomb in its middle region using a single photon test. | Session 46: Quantum Foundations |

691 | Quantum mysteries for anybody: Solved | Stuckey, William | I will show how conservation per no preferred reference frame (NPRF) answers that challenge, but still leaves a mystery for those who seek dynamical explanation via hidden variables or ‘causal influences’. | Session 46: Quantum Foundations |

692 | Time in Quantum Information | Ansari, Mohammad; van Steensel, Alwin; Nazarov, Yuli | I use a newly-developed replica trick formalism, namely ‘Multiparallel World (MW)’ formalism, that revolutionizes the theory. | Session 46: Quantum Foundations |

693 | Violations of macroscopic local reality, time and the Q-function | Reid, Margaret; Thenabadu, Manushan; Drummond, Peter | This motivates us to consider a model of reality based on the Q function. | Session 46: Quantum Foundations |

694 | Asymmetry in cause and effect in a quantum world | Thompson, Jayne | How can we observe an asymmetry in the temporal order of events when physics at the quantum level is time-symmetric? | Session 46: Quantum Foundations |

695 | Time operators and time crystals: self-adjointness by topology change | Nakatsugawa, Keiji; Fujii, Toshiyuki; Saxena, Avadh; Tanda, Satoshi | In this presentation, we investigate time operators in the context of quantum time crystals in ring systems [1,2]. | Session 46: Quantum Foundations |

696 | Classically-forbidden probability flow in the quantum reentry problem | Goussev, Arseni | In my talk, I will provide another clear-cut demonstration of nonconstancy of the direction of motion of a free particle. | Session 46: Quantum Foundations |

697 | Indefinite Causal Orderings for Quantum Depolarizing Channel Identification | Frey, Michael | The present work compares the effectiveness (QFI) of disparate competing ICOs for probing the qudit depolarizing channel. | Session 46: Quantum Foundations |

698 | Contextuality in non-interacting measurement | Greenfield, Sacha; Waegell, Mordecai; Dressel, Justin | We confirm this suspicion for the case of imbalanced beam splitters and discuss the exception that admits a noncontextual model. | Session 46: Quantum Foundations |

699 | A tight quantum speed limit for open quantum dynamics | Maleki, Yusef | In this work, we present a new quantum speed limit, which resolves both tightness and computability issues. | Session 46: Quantum Foundations |

700 | The Heisenberg Interpretation of Quantum Mechanics | Nikkhah Shirazi, Armin | In this talk, we present a concrete implementation of this distinction into the quantum formalism, resulting in what will be called the Heisenberg interpretation of quantum mechanics. | Session 46: Quantum Foundations |

701 | Experimental Comparison of Bohm-like Theories with Different Ontologies | Pang, Arthur; Ferretti, Hugo; Lupu-Gladstein, Noah; Tham, Weng-Kian; Brodutch, Aharon; Bonsma-Fisher, Kent; Sipe, John; Steinberg, Aephraim | In this paper we experimentally show how the two theories lead to different ontological descriptions. | Session 46: Quantum Foundations |

702 | Quantum Mechanical Reset-Observer Reset, not Observation, results in QM Wave-Particle Duality in Multi-Slit experiments | Alpert, Martin | Quantum Mechanical Reset-Observer Reset, not Observation, results in QM Wave-Particle Duality in Multi-Slit experiments | Session 46: Quantum Foundations |

703 | Challenges and opportunities for hybrid quantum-classical machine learning and optimization | Mohseni, Masoud | We introduce several new techniques for quantum circuit learning on Noisy Intermediate-Scale Quantum (NISQ) processors. | Session 47: Quantum Machine Learning |

704 | Variational Quantum Unsampling on an Photonic Quantum Processor | Carolan, Jacques; Mohseni, Masoud; Olson, Jonathan; Prabhu, Mihika; Chen, Changchen; Bunandar, Darius; Niu, Murphy; Harris, Nicholas; Wong, Franco; Hochberg, Michael; Lloyd, Seth; Englund, Dirk | Here, we introduce the Variational Quantum Unsampling (VQU) protocol, a nonlinear quantum neural network approach for verification and inference of near-term quantum circuits outputs. | Session 47: Quantum Machine Learning |

705 | Quantum Hamiltonian-Based Models and the Variational Quantum Thermalizer Algorithm | Verdon, Guillaume; Marks, Jacob; Nanda, Sasha; Leichenauer, Stefan; Hidary, Jack | We introduce a new class of generative quantum-neural-network-based models called Quantum Hamiltonian-Based Models (QHBMs). | Session 47: Quantum Machine Learning |

706 | Variational Fast Forwarding for Quantum Simulation Beyond the Coherence Time | Sornborger, Andrew; Cirstoiu, Cristina; Holmes, Zoe; Iosue, Joseph; Cincio, Lukasz; Coles, Patrick | Here, we present a hybrid quantum-classical algorithm, called Variational Fast Forwarding (VFF), for decreasing the quantum circuit depth of quantum simulations. | Session 47: Quantum Machine Learning |

707 | Stochastic Gradient Descent for Hybrid Quantum-Classical Optimization | Wilde, Frederik; Sweke, Ryan; Meyer, Johannes; Schuld, Maria; Fährmann, Paul; Meynard-Piganeau, Barthélémy; Eisert, Jens | In this work, we investigate the fact that the estimation of these quantities on quantum hardware leads to a form of stochastic gradient descent. | Session 47: Quantum Machine Learning |

708 | Robust and efficient algorithms for high-dimensional black-box quantum optimization | Leng, Zhaoqi; Mundada, Pranav; Ghadimi, Saeed; Houck, Andrew | We prove the asymptotic convergence of our algorithms in a convex setting, and we benchmark them against other gradient-based optimization algorithms on non-convex optimal control tasks. | Session 47: Quantum Machine Learning |

709 | A Hybrid Quantum-Classical Algorithm for Training Quantum Boltzmann Machines | Zoufal, Christa; Lucchi, Aurélien; Woerner, Stefan | In this work, we use variational quantum Gibbs state preparation to enable gate-based Quantum Boltzmann Machines which can be trained with the true loss function. | Session 47: Quantum Machine Learning |

710 | Quantum classifier with tailored quantum kernel | Park, Kyungdeock; Blank, Carsten; RHEE, June-Koo(KEVIN); Petruccione, Francesco | We present a distance-based quantum binary classifier whose kernel is based on the quantum state fidelity between training and test data. | Session 47: Quantum Machine Learning |

711 | Machine learning with solid-state NMR using quantum kernel | Kusumoto, Takeru; Mitarai, Kosuke; Negoro, Makoto; Fujii, Keisuke; Kitagawa, Masahiro | We propose to map an input to a feature space by input-dependent Hamiltonian evolution, and the kernel is estimated by the interference of the evolution. | Session 47: Quantum Machine Learning |

712 | Hybrid quantum-classical algorithms for generative models | Bian, Teng; Kais, Sabre | We propose a new hybrid quantum-classical circuit design for one major problem from machine learning aspect: generative models. | Session 47: Quantum Machine Learning |

713 | Quantum-tailored machine-learning architectures | Genois, Elie; Di Paolo, Agustin; Blais, Alexandre; Gross, Jonathan | To this end, we introduce a machine-learning architecture for inferring the dynamics of a quantum device from time-series measurement data. | Session 47: Quantum Machine Learning |

714 | Scalable Quantum State Tomography with Attention Network | Cha, Peter; Carrasquilla, Juan; Ginsparg, Paul; Kim, Eun-Ah | In this work, we demonstrate that an attention mechanism-based generative network, based on the model proposed in “Attention is all you need’’ by Vishwani et al (2017), can outperform previous neural network based approaches to quantum state tomography. | Session 47: Quantum Machine Learning |

715 | Implementing perceptron models with qubits | Wiersema, Roeland; Kappen, Hilbert | We propose a method for learning a quantum probabilistic model of a perceptron. | Session 47: Quantum Machine Learning |

716 | Advances in Quantum Reinforcement Learning | Dunjko, Vedran | Advances in Quantum Reinforcement Learning | Session 47: Quantum Machine Learning |

717 | Artificial Spiking Quantum Neural Networks | Kristensen, Lasse; Degroote, Matthias; Wittek, Peter; Aspuru-Guzik, Alan; Zinner, Nikolaj | In this talk, we will present a class of simple quantum spin-network models inspired by this classical paradigm, combining both an explicit neural network structure and explicit temporality through quantum evolution, and with the inherent ability to operate on quantum data as input. | Session 47: Quantum Machine Learning |

718 | A Path Towards Obtaining Quantum Advantage in Training Classical Deep Generative Models with Quantum Priors | Vinci, Walter; Buffoni, Lorenzo; Sadeghi, Hossein; O’Connor, Daniel; Andriyash, Evgeny; Amin, Mohammad | A class of quantum-classical hybrid machine-learning algorithms can be obtained by integrating classical deep generative models with quantum probability distributions as ‘priors’ over their latent variables. | Session 47: Quantum Machine Learning |

719 | Experimental demonstration of quantum-enhanced machine learning in NV center system | Zhang, Wengang; Ouyang, Xiaolong; Huang, Xianzhi; Deng, Dongling; Duan, Luming | We design efficient methods to prepare the initial electron-nuclear entangled state within the coherence time T 2* of the electron spin, and then compute the distance between the test vector and the center of each class by measuring the level population through maximum likelihood estimation. | Session 47: Quantum Machine Learning |

720 | Cost function embedding and dataset encoding for machine learning with parameterized quantum circuits | Cao, Shuxiang; Wossnig, Leonard; Vlastakis, Brian; Leek, Peter; Grant, Edward | In this talk, we introduce a routine to embed a cost function for machine learning into a quantum circuit, which accepts a training dataset encoded in superposition or an easily preparable mixed state. | Session 47: Quantum Machine Learning |

721 | Physical-Layer Supervised Learning Assisted by an Entangled Sensor Network | Zhuang, Quntao; Zhang, Zheshen | We introduce supervised learning assisted by an entangled sensor network (SLAEN) as a means to carry out SL tasks at the physical layer. | Session 47: Quantum Machine Learning |

722 | Quantum-inspired nonlocal parallel tempering with approximate tensor network contractions | Mohseni, Masoud; Eppens, Daniel; Rams, Marek; Boixo, Sergio; Neven, Hartmut | Specifically we provide two new cluster Monte Carlo techniques in which we combine tensor network contractions with “parallel tempering” (PT). | Session 47: Quantum Machine Learning |

723 | Generative quantum models over tensor network architectures | Najafi, Khadijeh; Azizi, Ahmadreza; Fuertes, Carlos; Stoudenmire, Miles; Mohseni, Masoud | Inspired by the probabilistic nature of quantum mechanics, we employ a generative model, known as the "Born machine". | Session 47: Quantum Machine Learning |

724 | RNN-VQE: a machine learning approach to generating variational ansatze | Warren, Ada; Zhu, Linghua; Tang, Ho Lun; Najafi, Khadijeh; Barnes, Edwin; Economou, Sophia | Here we present RNN-VQE, a machine learning model which uses recurrent neural networks to learn and quickly generate effective variational ansatze for VQE. | Session 47: Quantum Machine Learning |

725 | Measuring Correlation Scaling in Images via Logistic Regression | Convy, Ian; Huggins, William; Whaley, Birgitta | We find that our model can capture the scaling behavior of the Markov random fields even with hundreds of pixels, while the large MI values found in CIFAR and MNIST remain challenging to reproduce. | Session 47: Quantum Machine Learning |

726 | Quantum neural network for generating quantum states | Xia, Rongxin; Kais, Sabre | In this work, we give a new contruction of quantum neural network to introduce non-linear activation functions. | Session 47: Quantum Machine Learning |

727 | Gauge Enhanced Quantum Criticality and Time Reversal Domain Wall: SU(2) Yang-Mills Dynamics with Topological Terms | Zheng, Yunqin; You, Yizhuang; Wang, Juven | We focus on two possible scenarios: 1) time reversal symmetry is spontaneously broken by the two confining vacua, and 2) the low energy theory describes a U(1) spin liquid which is deconfined and gapless while preserving time reversal symmetry. | Session 47: Quantum Machine Learning |

728 | Robust Decomposition of Quantum States | Moussa, Jonathan | We show that quantum states over multiple subsystems can be recursively decomposed into states on one fewer subsystem and quantum operations that extend the state onto the omitted subsystem. | Session 47: Quantum Machine Learning |

729 | Quantum sensing beyond the standard quantum limit with 2D arrays of trapped ions | Gilmore, Kevin; Affolter, Matthew; Jordan, Elena; Lewis-Swan, Robert; Barberena, Diego; Shankar, Athreya; Holland, Murray; Rey, Ana Maria; Bollinger, John | We present experiments investigating the limits of electric field sensing via the excitation of the center-of-mass (COM) motion of 100s of ions in a 2D crystal. | Session 48: Quantum Measurement and Sensing |

730 | Spin-squeezing using optimized parametric driving | Groszkowski, Peter; Leroux, Catherine; Govia, Luke; Clerk, Aashish | In this talk we consider a parametrically driven cavity, coupled to a spin ensemble. | Session 48: Quantum Measurement and Sensing |

731 | Detecting spin polarization in 2D MoSe2 with nitrogen vacancy centers in diamond | Dwyer, Bo; Andersen, Trond; Scuri, Giovanni; Taniguchi, Takashi; Watanabe, Kenji; Kim, Philip; Park, Hongkun; Lukin, Mikhail | We report on progress towards the measurement of optically induced spin polarization in hole doped MoSe2 using nitrogen vacancy centers in diamond as nanoscale magnetic field probes. | Session 48: Quantum Measurement and Sensing |

732 | Observation of ac Photocurrent Vortices in Monolayer MoS2 Using NV Centers | Jerger, Paul; Zhou, Brian; Lee, Kan-Heng; Fukami, Masaya; Mujid, Fauzia; Park, Jiwoong; Awschalom, David | We demonstrate a contact-free method to spatially resolve photocurrents using nitrogen-vacancy (NV) centers in diamond, and discover that optical excitation of MoS 2 produces photocurrent vortices via the Nernst effect. | Session 48: Quantum Measurement and Sensing |

733 | Electric Field Sensing Using an NV Center Under Perpendicular Magnetic Field | Qiu, Ziwei; Hamo, Assaf; Vool, Uri; Pierce, Andrew; Xue, Ruolan; Zhou, Tony; Yacoby, Amir | Here we explored electric field sensing using an NV in the presence of a strong magnetic field acting perpendicular to the NV axis. | Session 48: Quantum Measurement and Sensing |

734 | Diamond parabolic reflectors for nanoscale quantum sensing | Shields, Brendan; Hedrich, Natascha; Rohner, Dominik; Batzer, Marietta; Maletinsky, Patrick | We address these challenges with all-diamond parabolic scanning probes containing single NVs. | Session 48: Quantum Measurement and Sensing |

735 | Extending the quantum coherence of a near-surface qubit by coherently driving the paramagnetic surface environment | Bluvstein, Dolev; Zhang, Zhiran; McLellan, Claire; Williams, Nicolas; Jayich, Ania | Here we show that the coherence time of a near-surface qubit is increased by coherent radio-frequency driving of surface electron spins, where we use a diamond nitrogen-vacancy (NV) center as a model qubit [1]. | Session 48: Quantum Measurement and Sensing |

736 | Observation of a quantum phase from classical rotation of a single spin | Wood, Alexander; Hollenberg, Lloyd; Scholten, Robert; Martin, Andy | The theory of angular momentum connects physical rotations and quantum spins together at a fundamental level. | Session 48: Quantum Measurement and Sensing |

737 | Long-living coherences and magnetic sensing with strongly-coupled quantum spins driven by pulse trains | Dobrovitski, Viatcheslav; Hahn, Walter | In this work, we present the protocols that employ the long-living coherences for quantum-assisted sensing of ac magnetic fields. | Session 48: Quantum Measurement and Sensing |

738 | Phase-estimation optimization in GaAs quantum dots | Gutierrez-Rubio, Angel; Stano, Peter; Loss, Daniel | We address the optimization of phase estimation in the context of GaAs quantum dots [1]. | Session 48: Quantum Measurement and Sensing |

739 | Imaging the crossover between ohmic and hydrodynamic electron flow in graphene with a single spin magnetometer | Jenkins, Alec; Baumann, Susanne; Meynell, Simon; Zhou, Haoxin; Yang, Daipeng; Taniguchi, Takashi; Watanabe, Kenji; Lucas, Andrew; Young, Andrea; Jayich, Ania | Our imaging technique provides a direct observation of collision-dominated electron transport. | Session 48: Quantum Measurement and Sensing |

740 | Sensing graphene density-of-states using a high-impedance resonator | Boettcher, Charlotte; Vool, Uri; Wang, Joel; Calusine, Greg; Kim, David; Rosenberg, Danna; Yoder, Jonilyn; Yacoby, Amir; Oliver, William | We propose to use this technique to study condensed-matter systems, and particularly the properties of graphene in the quantum Hall regime. | Session 48: Quantum Measurement and Sensing |

741 | Atomic-scale imaging of large nuclear-spin clusters using a quantum sensor | Taminiau, Tim Hugo | We present a new multidimensional spectroscopy method that isolates individual nuclearnuclear spin interactions with high spectral resolution (< 80 mHz) and high accuracy (2 mHz). | Session 48: Quantum Measurement and Sensing |

742 | Optimal approximate quantum error correction for quantum metrology | Zhou, Sisi; Jiang, Liang | Here we propose an optimal approximate quantum error correction (AQEC) strategy asymptotically saturating the precision lower bound in the most general adaptive parameter estimation scheme where arbitrary and frequent quantum controls are allowed. | Session 48: Quantum Measurement and Sensing |

743 | Multi-parameter metrology with the Holevo Cramer Rao bound; an explicit 2-qubit 3-parameter bound | Friel, Jamie; Albarelli, Francesco; Datta, Animesh | In this work we show that the QFIM is an inadequate metric for multi-parameter problems. | Session 48: Quantum Measurement and Sensing |

744 | Parametrically-enhanced quantum sensing with effective non-Hermitian lattice dynamics | McDonald, Alexander; Clerk, Aashish | Here, we show how to harness the unusual lattice physics to build quantum sensing platforms with remarkable properties. | Session 48: Quantum Measurement and Sensing |

745 | Metrology near exceptional points from superconducting circuits with loss | Harrington, Patrick; Abbasi, Maryam; Joglekar, Yogesh; Murch, Kater | We use post-selection to create an effective non-Hermitian Hamiltonian for a superconducting quantum circuit and measure the sensitivity of the circuit to a coherent drive for different system parameters. | Session 48: Quantum Measurement and Sensing |

746 | Macroscopic Quantum Tunneling Devices for Nanoscale Attonewton Force Sensing | Safvati, Benjamin; Chen, Yi-Ting; Brubaker, Morgan; Manoharan, Hari | This work presents a novel nanoscale probe of atomic-scale forces and enables new detection methods of the energy landscape in a Fermi gas. | Session 48: Quantum Measurement and Sensing |

747 | Dissipation-based quantum sensing of magnons | Wolski, Samuel; Lachance-Quirion, Dany; Tabuchi, Yutaka; Kono, Shingo; Usami, Koji; Nakamura, Yasunobu | We introduce a novel technique for quantum sensing of magnons by leveraging the quantum coherence of a superconducting qubit which interacts with a magnetostatic mode. | Session 48: Quantum Measurement and Sensing |

748 | Quantum sensing with superconducting microwave circuits | Partanen, Matti; Fedorov, Kirill; Pogorzalek, Stefan; Renger, Michael; Chen, Qi-Ming; Marx, Achim; Deppe, Frank; Gross, Rudolf | Here, we discuss a novel frequency-degenerate scheme for quantum sensing with superconducting microwave circuits. | Session 48: Quantum Measurement and Sensing |

749 | Quantum-Enhanced Noise Radar | Messaoudi, Nizar; Chang, Chung Wai; Vadiraj, A.M.; Bourassa, Jerome; Balaji, Bhashyam; Wilson, C.M. | The approach takes advantage of strong correlations that can be created in electromagnetic beams using quantum processes, through a form of entanglement. | Session 48: Quantum Measurement and Sensing |

750 | Mitigating back-action in parametric quantum amplifiers | Metelmann, Anja; Kamal, Archana | Here we present possible ways to face these challenges, and how to avoid unwanted back-action effects in engineered quantum systems. | Session 48: Quantum Measurement and Sensing |

751 | Near quantum limited Josephson traveling wave amplifiers I, Fabrication and characterization | Planat, Luca; Ranadive, Arpit; Dassonneville, Rémy; Puertas, Javier; Leger, Sebastien; Naud, Cécile; Buisson, Olivier; Guichard, Wiebke; Basko, Denis; Roch, Nicolas | In part I, we will present in detail, our simplified aluminum-based two-step fabrication technique for TWPAs with low footprint[1], and discuss their linear characterization[2]. | Session 48: Quantum Measurement and Sensing |

752 | Near quantum limited Josephson traveling wave amplifiers II Performance and further development | Ranadive, Arpit; Planat, Luca; Dassonneville, Remy; Puertas, Javier; Leger, Sebastien; Naud, Cécile; Buisson, Olivier; Hasch-Guichard, Wiebke; Basko, Denis; Roch, Nicolas | In part I, we will present in detail, our simplified aluminum-based two-step fabrication technique for TWPAs with low footprint[1], and discuss their linear characterization[2]. | Session 48: Quantum Measurement and Sensing |

753 | Heisenberg-limited single-mode quantum metrology in a superconducting circuit | Wang, Weiting; Wu, Yukai; Ma, Yuwei; Cai, Weizhou; Hu, Ling; Mu, Xianghao; Xu, Yuan; Chen, Zijie; Wang, Haiyan; Song, Yipu; Yuan, Haidong; Zou, Changling; Duan, Luming; Sun, Luyan | In this talk, we demonstrate such a single-mode phase estimation that approaches the Heisenberg limit (HL) unconditionally in a superconducting circuit by preparing the superpositions of Fock states (|0>+|N>) up to N=12. | Session 48: Quantum Measurement and Sensing |

754 | Quantum Metrology in the Era of Quantum Information | Demkowicz-Dobrzanski, Rafal | The theory developed allows to determine whether the Heisenberg scaling of precision is possible for a quantum sensor subject to a general Markovian noise. | Session 48: Quantum Measurement and Sensing |

755 | Observing a Topological Transition in Weak-Measurement-Induced Geometric Phases | Wang, Yunzhao; Snizhko, Kyrylo; Romito, Alessandro; Gefen, Yuval; Murch, Kater | To experimentally measure this transition, we employ quantum non-demolition measurement of a superconducting transmon circuit in the strong dispersive regime. | Session 48: Quantum Measurement and Sensing |

756 | Microscopic magnetometry of neurons using a superconducting flux qubit | Toida, Hiraku; Sakai, Koji; Mahboob, Imran; Teshima, Tetsuhiko; Kakuyanagi, Kousuke; Saito, Shiro | We have developed a microscopic magnetometer based on a superconducting flux qubit [1]. | Session 48: Quantum Measurement and Sensing |

757 | High contrast dual-mode optical and hyperpolarized 13C magnetic resonance imaging in diamond particles | Lv, Xudong; Walton, Jeffrey; Druga, Emanuel; Wang, Fei; Aguilar, Alessandra; McKnelly, Tommy; Nazaryan, Raffi; Wu, Lan; Shenderova, Olga; Vigneron, Daniel; Meriles, Carlos; Reimer, Jeffrey; Pines, Alexander; Ajoy, Ashok | In this work, we integrate optical and MR imaging in diamond particles endowed with a high density of quantum defects, Nitrogen Vacancy (NV) centers. | Session 48: Quantum Measurement and Sensing |

758 | Expanding the possibility of quantum metrology with a mixture of superpositions of marcoscopically distinct states | Tatsuta, Mamiko; Matsuzaki, Yuichiro; Shimizu, Akira | As a concrete example, we propose a protocol to generate a mixed GCS at finite temperature with donor spins in silicon. | Session 48: Quantum Measurement and Sensing |

759 | Weak Measurements of a Superconducting Qubit Reconcile Incompatible Observables | Monroe, Jonathan; Lee, Taeho; Yunger Halpern, Nicole; Murch, Kater | We find that a weak measurement can reconcile the incompatibility of two strong measurements via the weak measurement’s backaction. | Session 48: Quantum Measurement and Sensing |

760 | Control-enhanced quantum parameter estimation through reinforcement learning | Xu, Han; Wang, Xin | Here we show an efficient way to identify the controls through reinforcement learning that can improve the precision for both single-parameter estimation and multi-parameter estimation. | Session 48: Quantum Measurement and Sensing |

761 | Optimal protocols for simultaneous measurement of multiple analytic functions with quantum sensor networks | Bringewatt, Jacob; Niroula, Pradeep; Bienias, Przemyslaw; Gorshkov, Alexey | We consider the optimal bound with respect to different figures of merit for simultaneous measurement of multiple such analytic functions and propose protocols to achieve these bounds and thus Heisenberg scaling in the mean square error. | Session 48: Quantum Measurement and Sensing |

762 | Optimal control for quantum detectors | Titum, Paraj; Schultz, Kevin; Quiroz, Gregory; Clader, David | We identify, under modest assumptions about the statistical properties of the signal and noise, the optimal control to detect an external signal in the presence of background noise using a quantum sensor. | Session 48: Quantum Measurement and Sensing |

763 | Optimal Control and Glassiness in Quantum Sensing | Timms, Christopher; Kolodrubetz, Michael | We show that this added complexity translates into both improved sensitivity and qualitative modifications of the control landscape. | Session 48: Quantum Measurement and Sensing |

764 | Statistical Certification of Majorana fermions | Irfan, Abu Ashik Md.; Mayer, Karl; Ortiz, Gerardo; Knill, Emanuel | We present a quantum self-testing protocol that uses minimal assumptions and establishes strong conditions for Majorana fermion detection. | Session 48: Quantum Measurement and Sensing |

765 | Demonstration and Application of Long-lived state in a four-spin system hyperpolarized at room temperature | Miyanishi, Koichiro; Ichijo, Naoki; Motoyama, Makoto; Kagawa, Akinori; Negoro, Makoto; Kitagawa, Masahiro | In this work, we demonstrate the encoding of a four-nuclear-spin system hyperpolarized at room temperature into a long-lived state in a solution. | Session 48: Quantum Measurement and Sensing |

766 | Diamond quantum DC magnetometer with efficient digital signal processing | Masuyama, Yuta; Iwasaki, Takayuki; Hatano, Mutsuko; Ohshima, Takeshi | Here, we demonstrate an alternative method of digital signal processing with less computational resources than the Fourier transform. | Session 48: Quantum Measurement and Sensing |

767 | Magnetic Measurement of SPIONs using NVs in Diamond | Saleh Ziabari, Maziar; Kehayias, Pauli; Henshaw, Jacob; Lu, Tzu-Ming; Harris, Charles; Bielejec, Edward; Huber, Dale; Acosta, Victor; Lilly, Michael; Mounce, Andrew | We characterize the magnetic properties of SPIONs of varying size and density, deposited on the surface of NV implanted diamond. | Session 48: Quantum Measurement and Sensing |

768 | Imaging nanoscale volumes of single spins with shallow nitrogen-vacancy quantum spin sensors in diamond | Zhang, Zhiran; Bluvstein, Dolev; Williams, Nicolas; Jayich, Ania | Here we present NV-based imaging of electron spins patterned on the nanoscale structure, where we employ DNA origami, a powerful molecular self-assembly platform, to enable bottom-up patterning of single spin-containing molecules. | Session 48: Quantum Measurement and Sensing |

769 | Time-resolved diamond magnetic microscopy of superparamagnetic nanoparticles | Ristoff, Nate; Laraoui, Abdelghani; Fescenko, Ilja; Damron, Joshua; Mosavian, Nazanin; Smits, Janis; Jarmola, Andrey; Kehayias, Pauli; Salehziabari, Maziar; Mounce, Andrew; Huber, Dale; Acosta, Victor | We report progress on a nitrogen vacancy (NV) center widefield magnetic microscope which measures the Neel relaxation and hysteresis curve of many single magnetic nanoparticles. | Session 48: Quantum Measurement and Sensing |

770 | Analyzing the efficacy and work extraction of a quantum Maxwell’s demon | Song, Xingrui; Naghiloo, Mahdi; Murch, Kater | Here, we carefully analyze the relation between these two quantities, and find that they are not maximized simultaneously, requiring different feedback protocols. | Session 49: Quantum Thermodynamics |

771 | Simulating a quantum heat engine on transmon qubits | Materise, Nicholas; Kapit, Eliot | We devise a scheme to simulate a quantum heat engine using in an array of flux-tunable transmon qubits. | Session 49: Quantum Thermodynamics |

772 | Macroscopic Thermodynamic Reversibility in Quantum Many-Body Systems | Faist, Philippe; Sagawa, Takahiro; Kato, Kohtaro; Nagaoka, Hiroshi; Brandão, Fernando | The resource theory of thermal operations, an established model for small-scale thermodynamics, provides an extension of equilibrium thermodynamics to nonequilibrium situations. | Session 49: Quantum Thermodynamics |

773 | What is Quantum Thermodynamics? | Deffner, Sebastian | In this talk, we will outline a novel conceptual framework of an emerging theory, Quantum Thermodynamics, and illustrate its applicability, mindset, and questions with a few pedagogical examples. | Session 49: Quantum Thermodynamics |

774 | Entanglement transport and thermalization in an isolated quantum spin chain | Tsuchiya, Shunji; Yoshii, Ryosuke | In this work, we study transport of entanglement entropy (EE) in the Ising model with the next-nearest-neighbor interaction as well as the transverse and longitudinal magnetic fields. | Session 49: Quantum Thermodynamics |

775 | Characterizing complexity of many-body quantum dynamics by higher-order eigenstate thermalization | Kaneko, Kazuya; Iyoda, Eiki; Sagawa, Takahiro | We propose a higher-order generalization of the ETH, named by the k-ETH ( k=1, 2,…) , which provides a unified view on the above two concepts. | Session 49: Quantum Thermodynamics |

776 | Collective phenomena in quantum thermodynamics: from mitigation to amplification of the baths’ action | Lombard Latune, Camille; Sinayskiy, Ilya; Petruccione, Francesco | In order to understand better why and when such enhancements can happen, we analyse in details the energetic, entropic, and more generally thermodynamic consequences of collective coupling between an ensemble of identical systems (spin or atoms) and their bath. | Session 49: Quantum Thermodynamics |

777 | Thermalization of a qubit strongly interacting with a bosonic environment | Orman, Patrick; Mitchell, Dexter; Kawai, Ryoichi | Based on the theory of environment-induced decoherence, we introduce a couple of propositions: (1) in the strong coupling limit, the Gibbs state is projected to the convex hull spanned by the pointer basis, which necessarily increases the system entropy, and (2) the transition from the Gibbs state to the pointer limit takes place along the projection line perpendicular to the convex hull. | Session 49: Quantum Thermodynamics |

778 | Kinetics of many-body reservoir engineering | Ribeiro, Hugo; Marquardt, Florian | Here, we show that it is possible to cool a reservoir engineered many-body system with a well-defined chemical potential if the coupling with the reservoir is a density-density type coupling. | Session 49: Quantum Thermodynamics |

779 | Topological effects in quantum thermodynamics | Stafford, Charles; Xu, Yiheng; Evers, Ferdinand | Topological effects in quantum thermodynamics | Session 49: Quantum Thermodynamics |

780 | Fluctuations in stored work bound the charging power of quantum batteries | Garcia-Pintos, Luis; Hamma, Alioscia; Del Campo, Adolfo | We investigate the connection between the charging power of a quantum battery and the fluctuations of the work stored in it. | Session 49: Quantum Thermodynamics |

781 | Thermodynamics features of quantum memristors | Céleri, Lucas; Sanz, Mikel; Solano, Enrique; Landi, Gabriel | Here we describe such devices as a kind of thermodynamic engine operated by a Maxwell demon, but, instead of work, the output of such engine is non-Markovianity (time correlations), that can be employed to power quantum computation, for instance. | Session 49: Quantum Thermodynamics |

782 | Heat Transfer in Mesoscopic Systems | Weiderpass, Gabriel; Monteiro, Gustavo; Caldeira, Amir | In this talk, we present an analytical solution for the heat flux along a harmonic chain connecting two identical reservoirs at different temperatures, in the stationary regime. | Session 49: Quantum Thermodynamics |

783 | Anomalous Charge Noise in Superconducting Qubits | Wilen, Chris; Christensen, Bradley; Opremcak, Alexander; Riswadkar, Ameya; Faoro, Lara; Ioffe, Lev; McDermott, Robert | We describe experiments to probe fluctuations in offset charge in weakly charge-sensitive superconducting qubits that depart from the transmon regime. | Session 50: Qubit Coherence and Noise Characterization |

784 | Phonon traps reduce the quasiparticle density in superconducting circuits | Valenti, Francesco; Henriques, Fabio; Charpentier, Thibault; Lagoin, Marc; Gouriou, Clement; Martínez, Maria; Cardani, Laura; Vignati, Marco; Gruenhaupt, Lukas; Gusenkova, Daria; Ferrero, Julian; Skacel, Sebastian; Wernsdorfer, Wolfgang; Ustinov, Alexey; Catelani, Gianluigi; Sander, Oliver; Pop, Ioan-Mihai | Indeed, we demonstrate that surrounding high impedance resonators made of granular aluminum (grAl) with lower gapped thin film aluminum islands increases the internal quality factors of the resonators in the single photon regime, suppresses the noise, and reduces the rate of observed QP bursts [2]. | Session 50: Qubit Coherence and Noise Characterization |

785 | Photon-assisted charge-parity switches in superconducting qubits | Serniak, Kyle; Houzet, Manuel; Catelani, Gianluigi; Diamond, Spencer; Hays, Max; Fatemi, Valla; Devoret, Michel; Glazman, Leonid | Here we identify a mechanism by which stray photons, with energy large enough to break Cooper pairs, can cause decoherence in superconducting qubits. | Session 50: Qubit Coherence and Noise Characterization |

786 | Microscopic charging and in-gap states in superconducting granular aluminum | Yang, Fang; Storbeck, Tim; Gozlinski, Thomas; Gruenhaupt, Lukas; Pop, Ioan-Mihai; Wulfhekel, Wulf | Here we present scanning tunneling microscope measurements of the local electronic structure of superconducting grAl and we confirm an increased superconducting gap in the grains of films with ρ ≈ 300 μΩcm and ρ ≈ 2000 μΩcm. | Session 50: Qubit Coherence and Noise Characterization |

787 | Probing non-equilibrium quasiparticle populations in superconducting quantum circuits. | Farmer, James; Hartsell, Darian; Zhang, Haimeng; Vlachos, Evangelos; Levenson-Falk, Eli | We discuss these single-shot fidelity measurements of QPs trapping in the junctions of a nanobridge SQUID embedded in a superconducting resonator. | Session 50: Qubit Coherence and Noise Characterization |

788 | Improved material loss measurement using cryogenic resonator testbed | Wang, Haozhi; McRae, Corey Rae; Mullins, Keegan; Mutus, Josh; Fork, David; Pappas, David | In this talk, we will compare the results of different measurement configurations, especially for input and output line filtering and isolation, and quantify the accuracy of loss measurement in order to identify best practices for resonator measurement and setup procedures. | Session 50: Qubit Coherence and Noise Characterization |

789 | Detection of non-equilibrium quasiparticles in charge sensitive transmons | Kurter, Cihan; Sandberg, Martin; Adiga, Vivekananda; Minev, Zlatko; Finck, Aaron; Eddins, Andrew; Shelby, Robert; Brink, Markus; Chow, Jerry | Here, we study charge parity fluctuations in 2D transmon qubits with sufficiently strong coupling and low E J/E C ratio. | Session 50: Qubit Coherence and Noise Characterization |

790 | Experimental study of flux noise in nanowire transmons subject to an applied magnetic field | Stavenga, Thijs; Luthi, Florian; Vaal, Elmore; Aluko, Oluwatumininu; Krogstrup, Peter; DiCarlo, Leonardo | In this work, we experimentally investigate flux noise using an unconventional knob for circuit QED: an applied magnetic field. | Session 50: Qubit Coherence and Noise Characterization |

791 | Surface spin induced 1/f flux noise dependent on SQUID geometry (1) | Ding, Leon; Braumueller, Jochen; Vepsalainen, Antti; Sung, Youngkyu; Kjaergaard, Morten; Menke, Tim; Winik, Roni; Kim, David; Niedzielski, Bethany; Melville, Alexander; Yoder, Jonilyn; Hirjibehedin, Cyrus; Orlando, Terry; Gustavsson, Simon; Oliver, William | Here, we demonstrate the validity of this model by measuring the flux noise amplitudes of about 50 capacitively shunted flux qubits over a wide range of geometric SQUID parameters. | Session 50: Qubit Coherence and Noise Characterization |

792 | Surface spin induced 1/f flux noise dependent on SQUID geometry (2) | Braumueller, Jochen; Ding, Leon; Vepsalainen, Antti; Sung, Youngkyu; Kjaergaard, Morten; Menke, Tim; Winik, Roni; Kim, David; Niedzielski, Bethany; Melville, Alexander; Yoder, Jonilyn; Hirjibehedin, Cyrus; Orlando, Terry; Gustavsson, Simon; Oliver, William | Here, we measure the flux noise amplitudes of capacitively shunted flux qubits and study their dependence on geometric parameters of their SQUID loops. | Session 50: Qubit Coherence and Noise Characterization |

793 | Characterizing non-classical non-Gaussian noise: photon shot noise fluctuations | Wang, Yuxin; Clerk, Aashish | We extend the Keldysh approach for characterizing this quantum noise [1,2] to calculate its frequency-resolved third cumulant, the so-called bispectrum. | Session 50: Qubit Coherence and Noise Characterization |

794 | Identifying Noise Sources via Multi-level Quantum Noise Spectroscopy | Sung, Youngkyu; Vepsalainen, Antti; Braumüller, Jochen; Yan, Fei; Wang, Joel; Kjaergaard, Morten; Winik, Roni; Krantz, Philip; Bengtsson, Andreas; Kim, David; Melville, Alexander; Niedzielski, Bethany; Schwartz, Mollie; Yoder, Jonilyn; Orlando, Terry; Gustavsson, Simon; Oliver, William | Here, we develop and experimentally validate a multi-level QNS protocol using a superconducting transmon qubit as a spectrometer. | Session 50: Qubit Coherence and Noise Characterization |

795 | Measuring effective temperatures of qubits using correlations | Kulikov, Anatoly; Navarathna, Rohit; Fedorov, Arkady | We propose a new technique of finding the excited state population of a qubit using measurement correlations in time. | Session 50: Qubit Coherence and Noise Characterization |

796 | Photon Shot Noise Limited Charge Sensitivity in a Hybrid Quantum System | Kanhirathingal, Sisira; Blencowe, Miles; Brock, Benjamin; Rimberg, Alexander | We present a theoretical analysis of the photon shot noise limited charge sensitivity of the device, assuming a low average photon number drive. | Session 50: Qubit Coherence and Noise Characterization |

797 | Characterization of noise correlations in superconducting quantum circuits | Wang, Tenghui; Wu, Feng; Zhou, Jingwei; Deng, Hao; Zhang, Gengyan; Jiang, Xun; Yu, Wenlong; Ku, Hsiang-Sheng; Deng, Chunqing | Based on a weak measurement scheme [1], we present an experiment to detect high-order correlations in a superconducting circuit. | Session 50: Qubit Coherence and Noise Characterization |

798 | T1 of transmons with electrodes that have different gaps. | Li, Kungang; Wellstood, Frederick; Lobb, Christopher; Dutta, Sudeep; Zhang, Rui; Keshvari, Shahriar; Poppert, Dylan | We compared our T 1 vs T results to a model based on the behavior of nonequilibrium quasiparticles residing in the electrodes and extracted the energy gap and the density of the non-equilibrium quasiparticles. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

799 | Power and temperature dependence of High Q superconducting resonators | Alexander, Ashish; Weddle, Christopher; Richardson, Christopher | Here we propose a two temperature power and temperature dependent model to evaluate resonator losses that considers quasiparticle and phonon temperatures to be different. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

800 | Integration of InAs-Al Heterostructures into Microwave Circuit | Yuan, Joseph; Dartiailh, Matthieu; Mayer, William; Goss, Noah; Nguyen, Tri; Wickramasinghe, Kaushini; Sardashti, Kasra; Shabani, Javad | Here we present the integration of these InAs-Al heterostructures into microwave circuits such as Gatemon Qubits. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

801 | Preprocessing Method for Microwave Resonator Fitting | Mullins, Keegan; McRae, Corey Rae; Pappas, David; Mutus, Josh; Wang, Haozhi; Fork, David | We present a preprocessing method for S21 data from superconducting microwave resonators. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

802 | Materials Engineering in Superconducting Qubits | Place, Alexander; Smitham, Basil; Rodgers, Lila; Mundada, Pranav; Fitzpatrick, Mattias; Sussman, Sara; Premkumar, Anjali; Bryon, Jacob; Jaeck, Berthold; Cheng, Guangming; Babla, Harshvardhan; Madhavan, Trisha; Ferrenti, Austin; Gyenis, Andras; Cava, Robert; Yao, Nan; De Leon, Nathalie; Houck, Andrew | In this talk we again focus on materials engineering of qubits. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

803 | Observation of individual two-level defects at material surfaces using circuit QED | Kohler, Timothy; Hung, Chih-Chiao; Osborn, Kevin; Forouzani, Neda | In an aluminum thin film on sapphire substrate we observe individual surface TLS using a DC electric-field bias in an interdigitated shunting capacitor with a submicron linewidth and line spacing. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

804 | TBD | Rosenberg, Danna | TBD | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

805 | The dielectric dipper: a differential technique to measure dielectric loss tangents with high sensitivity | Read, Alexander; Li, Kaicheng; Chapman, Benjamin; Lei, Chan U; Jain, Vijay; Axline, Christopher; Frunzio, Luigi; Schoelkopf, Robert | We present experimental comparisons of common dielectric substrates measured using this method. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

806 | Transmon qubit in a magnetic field: Evolution of coherence and transition frequency | Weides, Martin; Schneider, Andre; Wolz, Tim; Pfirrmann, Marco; Spieker, Martin; Rotzinger, Hannes; Ustinov, Alexey | We report on spectroscopic and time-domain measurements on a fixed-frequency concentric transmon qubit in an applied in-plane magnetic field to explore its limits of magnetic field compatibility. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

807 | Design of The Merged Element Transmon Qubit | Park, Sungoh; Zhao, Ruichen; McRae, Corey Rae; Long, Junling; Zhao, Tongyu; Lake, Russell; Bal, Mustafa; Wang, Haozhi; Pappas, David | To circumvent this issue, we propose to engineer the device so that the electric field distribution is confined to junction dielectric by merging the capacitor and JJ into a single superconductor/dielectric/superconductor trilayer structure such that the frequency, anharmonicity, and E j/E c parameters are in the transmon regime. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

808 | Improving the performance of superconducting coplanar waveguide resonators using interface engineering | Banerjee, Archan; Alghadeer, Mohammed; Hajir, Ahemd; Kreikebaum, John Mark; Ogletree, Frank; Altoe, Virginia; Rao, Saleem; Siddiqi, Irfan | In this study, we explore the characterization and the fabrication of niobium coplanar waveguide resonators with more than 10 6 internal quality factor at single-photon-excitation power (measured at 100 mK) for a variety of different surface treatments. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

809 | Reliable Growth of TaN Superconducting Film with Atomic Layer Deposition for Quantum Circuit Applications | Song, Wonho; Jung, Sungchul; Kim, Junhyung; Choi, Gahyun; Lee, Joonyoung; Chong, Yonuk; Park, Kibog | In this work, several different thicknesses of TaN thin films are grown on SiO 2/Si or Si substrates with plasma enhanced ALD process using the Tris(diethylamido)(tert-butylimido)tantalum(TBTDET) precursor reacted with H 2 gas. | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

810 | Microwave Loss in High-Q Titanium Nitride Resonators | Zhang, Rui; Alexander, Ashish; Richardson, Christopher; Wellstood, Frederick; Palmer, Benjamin | We compare the measured Q data to a model based on loss from the interaction of the superconducting resonator with lossy two-level systems and separately to a model we have developed based on non-equilibrium quasiparticles accumulating in regions of the TiNx film with a lower superconducting gap (D). | Session 51: Superconducting Qubit Materials, Fabrication, and Coherence |

811 | Quantum Supremacy: Benchmarking the Sycamore Processor | Satzinger, Kevin | Here we report the use of a processor with 53 programmable superconducting qubits. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

812 | Quantum supremacy using the Sycamore processor | Neill, Charles | In this talk, I will focus on the hardware details of the Sycamore processor and how this device enabled supremacy-quality two-qubit gates. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

813 | Quantum simulation in circuit QED: Observation of quantum many-body effects due to zero point fluctuations in superconducting circuits – I: Theory | Roch, Nicolas; Leger, Sebastien; Puertas, Javier; Bharadwaj, Karthik Srikanth; Dassonneville, Remy; Delaforce, Jovian; Foroughi, Farshad; Milchakov, Vladimir; Planat, Luca; Buisson, Olivier; Naud, Cécile; Hasch-Guichard, Wiebke; Florens, Serge; Snyman, Izak | Quantum simulation in circuit QED: Observation of quantum many-body effects due to zero point fluctuations in superconducting circuits – I: Theory | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

814 | Quantum simulation in circuit QED: Observation of quantum many-body effects due to zero point fluctuations – II: Experiment | Leger, Sebastien; Puertas, Javier; Bharadwaj, Karthik Srikanth; Dassonneville, Remy; Delaforce, Jovian; Foroughi, Farshad; Milchakov, Vladimir; Planat, Luca; Buisson, Olivier; Naud, Cécile; Guichard, Wiebke; Florens, Serge; Snyman, Izak; Roch, Nicolas | Quantum simulation in circuit QED: Observation of quantum many-body effects due to zero point fluctuations – II: Experiment | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

815 | Analog quantum simulation of a Kondo impurity with superconducting circuits | Grabon, Nicholas; Kuzmin, Roman; Mehta, Nitish Jitendrakumar; Goldstein, Moshe; Manucharyan, Vladimir | This spin couples to a continuum of modes in the waveguide, which acts as the bath, thus completing the model. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

816 | Simulating a Dirac particle with coupled transmon circuits | Svetitsky, Elisha; Katz, Nadav | We map the Dirac equation of relativistic quantum mechanics in 3+1 dimensions onto a multi-level superconducting Josephson circuit. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

817 | Quantum Simulation of Hyperbolic Space with Circuit Quantum Electrodynamics: From Graphs to Geometry | Boettcher, Igor; Bienias, Przemyslaw; Belyansky, Ron; Kollar, Alicia; Gorshkov, Alexey | We give a quantum field theoretic perspective on recent breakthrough experiments in circuit quantum electrodynamics, where hyperbolic lattices are realized with superconducting resonators and photons are tricked into believing that space is hyperbolic. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

818 | Demonstration of programmable quantum simulations of lattice models using a superconducting parametric cavity | Busnaina, Jamal; Hung, Jimmy Shih-Chun; Moghaddam, M.V.; Chang, Chung Wai; Vadiraj, A.M.; Alaeian, Hadiseh; Rico, Enrique; Wilson, C.M. | In this talk, we present experimental results on a variety of different small lattice models. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

819 | Quantum simulation of a spin chain with superconducting circuits | Ficheux, Quentin; Somoroff, Aaron; Mehta, Nitish Jitendrakumar; Kuzmin, Roman; Martin, Ivar; Vavilov, Maxim; Manucharyan, Vladimir | Initial experimental efforts to simulate this model have focused on cold atoms [1] and trapped ion systems [2,3] with limited coupling strength imposed by the laws of nature. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

820 | Growth and preservation of entanglement in a many-body localized system | Chiaro, Ben; Foxen, Brooks; McEwen, Matthew; Martinis, John | We use programmable superconducting qubit quantum processors to provide a detailed survey of the many-body localized (MBL) phase for both 1D and 2D lattice geometries. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

821 | Approximating finite-temperature dynamic correlation functions on quantum computers | Cohn, Jeffrey; Najafi, Khadijeh; Jones, Barbara; Freericks, James | We present a framework aimed at alleviating this bottleneck by optimizing a series of approximations. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

822 | Band engineering for quantum simulation with superconducting circuits | Chiu, Christie; Houck, Andrew | Here I report on recent progress towards engineering flat bands for studies of strongly correlated many-body physics. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

823 | Propagation and Localization of Collective Excitations on a 24-Qubit Superconducting Processor | Ye, Yangsen | Here we construct a Bose-Hubbard ladder with a ladder array of 20 qubits. | Session 52: Superconducting Qubit Quantum Simulation and Algorithms |

824 | Control of Transmon Qubits using a Cryogenic CMOS Integrated Circuit | Bardin, Joseph | In this talk, we will present a review of recent work towards implementing a scalable cryogenic quantum control and readout system using silicon integrated circuit technology. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

825 | Kalman-based IQ Mixer Calibration for Circuit QED | Jolin, Shan; Borgani, Riccardo; Tholén, Mats; Haviland, David | In this talk we present some simple but elegant methods which do not require a spectrum analyzer, to calibrate both up and downconversion mixers in situ (i.e. without disconnecting the device under test). | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

826 | Reversible Fluxon Logic with shift registers | Wustmann, Waltraut; Osborn, Kevin | We apply a model developed to describe RFL dynamics. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

827 | Practical Microwave Direct Digital Synthesis for Superconducting Qubit Control | Kalfus, William; Lee, Diana; Fallek, Spencer; Ribeill, Guilhem; Wagner, Andrew; Gustafsson, Martin; Ohki, Thomas; Donovan, Brian; Ristè, Diego | To address this, we have incorporated custom superconducting qubit control logic into off-the-shelf hardware employing direct RF synthesis at 5 GHz for low-noise and low-latency pulse generation up to 7.5 GHz. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

828 | A scalable FPGA platform for qubit readout and control | Tholen, Mats; Borgani, Riccardo; Jolin, Shan; Haviland, David | We adapted the Xilinx Zynq Ultrascale+ RFSoC hardware platform by implementing firmware for pulsed control and readout of qubit circuits. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

829 | High-density cryogenic wiring for superconducting qubits | Weber, Steven; Cummings, John; Miloshi, Jovi; Thompson, Kyle; Rokosz, John; Kerman, Andrew; Oliver, William | We will describe the electrical performance of these cables, as well as other design considerations such as thermal management. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

830 | Single Flux Quantum based electronics for control and readout of superconducting qubits. | Castellanos-Beltran, Manuel; Sirois, Adam; Long, Junling; Fox, Anna; Schmidt, Dan; Dresselhaus, Paul; Hopkins, Peter; Ullom, Joel; Pappas, David; Benz, Samuel | In this talk we present an experimental demonstration generating spectroscopy tones at 4 K to measure a transmon qubit’s energy level spacings at 100 mK. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

831 | Unconditional reset of superconducting qubits and readout resonators using a quantum-circuit refrigerator | Sevriuk, Vasilii; Tuorila, Jani; Heinsoo, Johannes; Ockeloen-Korppi, Caspar; Ikonen, Joni; Tan, Kuan; Hyyppä, Eric; Silveri, Matti; Partanen, Matti; Jenei, Máté; Catto, Giacomo; Mörstedt, Timm; Grönberg, Leif; Goetz, Jan; Mottonen, Mikko | We discuss our latest results to this end. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

832 | Simple, smooth 50ns QND circuit-QED measurement pulses | Motzoi, Felix; Dickel, Christian; Buchmann, Lukas | We demonstrate a technique for greatly reducing the duration and error in circuit QED measurement tasks. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

833 | Predictive feedback for active noise canceling in superconducting quantum processors | Karamlou, Amir; Vepsalainen, Antti; Winik, Roni; Kim, David; Yoder, Jonilyn; Melville, Alexander; Niedzielski, Bethany; Orlando, Terry; Gustavsson, Simon; Oliver, William | In this work, we show how to efficiently estimate the noise spectrum experienced by the qubit, employ techniques from machine learning to predict the correlated noise in the future and use fast-feedback with an FPGA to cancel the noise. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

834 | QubiC – An open FPGA based Qubit Control system | Huang, Gang; Xu, Yilun; Naik, Ravi; Mitchell, Bradley; Santiago, David; Siddiqi, Irfan | In this talk, we describe the system structure, the firmware implementation and the design of the analog front end boards. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

835 | A Scalable Multi-Channel Cryogenic Controller for Spin Qubits/Transmons with Frequency Multiplexing Capability Implemented in Intel 22nm FinFET Technology | Patra, Bishnu; P. G. van Dijk, Jeroen; Subramanian, Sushil; Corna, Andrea; Xue, Xiao; Jeon, Charles; Sheikh, Farhana; Juarez Hernandez, Esdras; Perez Esparza, Brando; Rampurawala, Huzaifa; Carlton, Brent; Samkharadze, Nodar; Ravikumar, Surej; Nieva, Carlos; Kim, Sungwon; Lee, Hyung-Jin; Sammak, Amir; Scappucci, Giordano; Veldhorst, Menno; Vandersypen, Lieven; Babaie, Masoud; Sebastiano, Fabio; Charbon, Edoardo; Pellerano, Stefano | We have recently proposed to bring integrated electronics close to the qubits at cryogenic temperatures. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

836 | Design, Modeling, and Measurement of Through-Silicon Via (TSV) Structures for Superconducting Quantum Computing | Woods, Wayne; Rosenberg, Danna; Schwartz, Mollie; Yost, Donna; Yoder, Jonilyn; Oliver, William | We describe our electromagnetic modeling of TSV-embedded routing elements, and we demonstrate their incorporation into design and measurement of superconducting qubits. | Session 53: Superconducting Qubit Readout, Detection, and Classical Control Electronics |

837 | Scalable packaging for superconducting qubits with vertical wiring | Tamate, Shuhei; Tabuchi, Yutaka; Szikszai, Laszlo; Kusuyama, Koichi; Zuo, Kun; Hishida, Yuji; Qiu, Wei; Terai, Hirotaka; Ukibe, Masahiro; Fujii, Go; Makise, Kazumasa; Watanabe, Naoya; Kikuchi, Katsuya; Nakamura, Yasunobu | To implement realistic quantum error correction codes, such as surface codes, we aim at integrating a two-dimensional array of superconducting qubits in a scalable way. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

838 | Multilayer Microwave Integrated Quantum Circuits: Part 1 | Lei, Chan U; Krayzman, Lev; Ganjam, Suhas; Frunzio, Luigi; Schoelkopf, Robert | In this talk, we will present an overview of the MMIQC architecture and the ability to realize modular quantum networks. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

839 | Multilayer Microwave Integrated Quantum Circuits: Part 2 | Krayzman, Lev; Lei, Chan U; Ganjam, Suhas; Frunzio, Luigi; Schoelkopf, Robert | In this talk, we will present an indium bump-bonding approach to produce superconducting seams with RF conductance exceeding 10^10/Ωm. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

840 | Multilayer Microwave Integrated Quantum Circuits: Part 3 | Ganjam, Suhas; Lei, Chan U; Krayzman, Lev; Frunzio, Luigi; Schoelkopf, Robert | In this talk, we will demonstrate on-chip microwave resonant cavities with low-power quality factors exceeding 300 million. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

841 | Principles of Microwave Package Design for Superconducting Quantum Processors | Huang, Sihao; Lienhard, Benjamin; Kannan, Bharath; Braumüller, Jochen; Kim, David; Wang, Joel; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Orlando, Terry; Gustavsson, Simon; Oliver, William | We present results from simulations of these elements and corresponding physical measurements on a newly designed package. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

842 | 3D Integration with Protected Qubits | Premkumar, Anjali; Gyenis, Andras; Mundada, Pranav; Houck, Andrew | In this talk, we propose to use intrinsically protected qubits for 3D integration: resistance to dielectric loss allows for simple layered structures similar to classical 3D architectures. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

843 | Quantifying the impact of a caps and vias architecture for superconducting qubits | Jackson, Keith; Bestwick, Andrew; Caldwell, Shane; Reagor, Matthew | To enable this, we describe a chip architecture that combines superconducting caps with recessed cavities bump bonded to a quantum IC with superconducting vias. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

844 | Design Considerations for Near-term Quantum Processors | Stockklauser, Anna | This talk will address challenges and solutions in the design and fabrication of superconducting qubit-based quantum processors related to scaling, 3D integration, and device operation. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

845 | Cryogenic Thermalization Measurements of Microwave Attenuators | Maiti, Aniket; Jain, Vijay; Frunzio, Luigi; Schoelkopf, Robert | We thus study the thermalization of cryo-attenuators by using a coaxial stub cavity over-coupled to a microwave input line for absolute temperature measurement. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

846 | Dilution-equivalent solid-state chip refrigeration | Ronzani, Alberto; Lehtinen, Janne; Mykkanen, Emma; Kemppinen, Antti; Grönberg, Leif; Manninen, Antti; Prunnila, Mika | Here we present a multi-stage thermionic cooler, targeting the 1.5K to 100 mK range. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

847 | Hot electron measurements below 100 mK for quantum devices | Steffen, Zachary; Dutta, Sudeep; Zhang, Rui; Huang, Yizhou; Li, Kungang; Wellstood, Frederick; Palmer, Benjamin | In this talk, we will discuss ongoing measurements to more directly measure the electron temperature and find the electron-phonon coupling constant of NiCr. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

848 | Extending Superconducting Qubits Out of Plane (Part 1): Qubits with Air Bridge Crossovers in Multi-Tier Stacks | Yoder, Jonilyn; Mallek, Justin; Kim, David; Yost, Donna-Ruth; Calusine, Greg; Das, Rabindra; Day, Alexandra; Melville, Alexander; Niedzielski, Bethany; Rosenberg, Danna; Samach, Gabriel; Schwartz, Mollie; Weber, Steven; Oliver, William | We are developing heterogeneous 3D integration of a qubit tier combined with an interposer with high-aspect-ratio superconducting through-silicon vias and a superconducting multi-chip module. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

849 | Extending Superconducting Qubits Out of Plane (Part 2): Through-Silicon Vias | Mallek, Justin; Yoder, Jonilyn; Yost, Donna-Ruth; Das, Rabindra; Day, Alexandra; Rosenberg, Danna; Calusine, Greg; Cook, Matthew; Golden, Evan; Kim, David; Melville, Alexander; Niedzielski, Bethany; Schwartz, Mollie; Stull, Corey; Tolpygo, Sergey; Woods, Wayne; Oliver, William | To enable high connectivity of superconducting qubits we are utilizing heterogeneous 3D integration of a qubit tier, an interposer with high-aspect-ratio superconducting through-silicon vias (TSVs), and a superconducting multi-chip module. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

850 | Quantifying Losses in Transmon Qubits | Calusine, Greg; Woods, Wayne; Melville, Alexander; Serniak, Kyle; Kim, David; Yoder, Jonilyn; Oliver, William | As part of this approach, we develop the fabrication processes and EM modeling techniques necessary for accurately modeling dielectric losses. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

851 | Effects of surface treatments and packaging on transmon qubits | Mergenthaler, Matthias; Müller, Clemens; Ganzhorn, Marc; Paredes, Stephan; Müller, Peter; Filipp, Stefan; Fuhrer, Andreas | Here, we present our work towards understanding decoherence mechanisms in flux-tunable transmon qubits. | Session 54: Superconducting Qubits: 3D Integration and Cryogenic Packaging |

852 | QuCAT: superconducting quantum circuit analyzer tool in Python | Gely, Mario; Steele, Gary | In this talk, we present QuCAT, or "Quantum Circuit Analyzer Tool", an open-source framework to help in this task. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

853 | Quantization of Large Superconducting Circuits with Tensor Networks | Weippert, Matthew; Colladay, Kristina; Ferguson, David; Epstein, Ryan | We report on efficient quantum simulation of large superconducting circuits using matrix product states (MPS) and the density matrix renormalization group (DMRG) technique. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

854 | Tensor-network diagonalization of many-body superconducting qubits | Di Paolo, Agustin; Baker, Thomas; Foley, Alexandre; Senechal, David; Blais, Alexandre | We introduce a tensor-network method tailored to the simulation of large-scale superconducting quantum circuits. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

855 | Flux Dual Description of Noise-Insensitive Superconducting Qubits | Ferguson, David; Clarke, David; Epstein, Ryan; Khalil, Moe; Weiss, Daniel; Koch, Jens | This talk describes a method to transform the Hamiltonian of a superconducting circuit from the Cooper-pair number basis to the dual vortex-number basis. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

856 | Designing Better Superconducting Qubits using First-Principles Calculations and Theory | Griffin, Sinead | In this work, we combine first-principles calculations and effective models to describe key performance losses in niobium-based superconducting qubits. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

857 | Design and Analysis of Multi-Qubit Superconducting Chips for Extensible Surface Coding | Haider, Nadia; Bruno, Alessandro; Beekman, Marc; Kaminski, Piotr; DiCarlo, Leonardo | We present an effective numerical method to analyze qubit-qubit avoided crossings and two-qubit gate times in a superconducting multi-qubit chip. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

858 | Design and quantization of superconducting circuits | Minev, Zlatko; McConkey, Thomas; Solgun, Firat; Chow, Jerry; Gambetta, Jay; McKay, David | In this talk, we review some recent results on the comparison between several of the commonly used quantization and design approaches. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

859 | Derivation of the Hamiltonian of a flux qubit-LC oscillator circuit using the circuit variables | Yoshihara, Fumiki; Ashhab, Sahel; Fuse, Tomoko; Semba, Kouichi | We derive the Hamiltonian of a single-Josephson-junction flux qubit-LC oscillator circuit using the standard quantization procedure [1]. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

860 | Efficient Hamiltonian Parameter Estimation with Sequential Monte Carlo Technique | Béjanin, Jérémy; Earnest, Carolyn; Mariantoni, Matteo; Sanders, Yuval | Using tunable transmon superconducting qubits, we demonstrate a method to efficiently measure the parameters of these resonant couplings. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

861 | Universal Formalism and Software for Obtaining and Analyzing Hamiltonians of an Arbitrary Superconducting Circuits and Qubits. | Klots, Andrey; Ioffe, Lev; McDermott, Robert | We propose a mathematical formalism and software that allow to express Hamiltonian of any superconducting circuit in a standardized way. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

862 | Quantum landscape engineering of superconducting circuit ground states for higher-order coupler design | Menke, Tim; Hirjibehedin, Cyrus; Weber, Steven; Braumüller, Jochen; Vepsalainen, Antti; Winik, Roni; Samach, Gabriel; Kim, David; Melville, Alexander; Niedzielski, Bethany; Rosenberg, Danna; Schwartz, Mollie; Yoder, Jonilyn; Aspuru-Guzik, Alan; Gustavsson, Simon; Kerman, Andrew; Oliver, William | We propose a methodology for adding higher-order polynomial terms into the ground state energy versus flux by strongly coupling a series of rf SQUIDs. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

863 | Quantized Hodgkin-Huxley Model for Quantum Neurons | Gonzalez Raya, Tasio; Sanz, Mikel; Solano, Enrique | The Hodgkin-Huxley model describes the conduction of the nervous impulse through the axon, whose membrane’s electric response can be described by multiple connected electric circuits containing capacitors, voltage sources, and conductances. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

864 | Floquet theory for driven-dissipative dynamics of superconducting circuits | Le Calonnec, Camille; Petrescu, Alexandru; Blais, Alexandre | We developed a corrected numerical implementation of the Floquet-Markov Master Equation that exactly takes into account the effects of drives and apply it to study more accurately the dissipative dynamics of superconducting qubits. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

865 | Lifetime renormalization of driven transmon qubits and the classification of mechanisms for drive-induced energy relaxation | Tureci, Hakan; Petrescu, Alexandru; Malekakhlagh, Mohammad Moein | In two recent papers [1,2] we have shown that the leading mechanism responsible for the enhancement of energy relaxation times of weakly anharmonic qubits is the presence of number non-conserving terms in the Josephson potential, which activate additional multi-photon and qubit-cavity correlated relaxation channels in the presence of drives. | Session 55: Superconducting Qubits: Circuit Theory, Hamiltonian Analysis and Design Tools |

866 | Two-qubit gate with a parity-violated superconducting qubit | Noguchi, Atsushi; Kono, Shingo; Masuda, Shumpei; Heya, Kentaro; Wolski, Samuel; Takahashi, Hiroki; Sugiyama, Takanori; Osada, Alto; Lachance-Quirion, Dany; Nakamura, Yasunobu | Here we propose a parity-violated superconducting qubit, which enables us to achieve a strong parametric coupling with a neighboring qubit based on the second-order nonlinearity. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

867 | Characterization and Tuneup of High-Fidelity Two-Qubit Operations on a Parametrically Driven Gate | Warren, Christopher; Bengtsson, Andreas; Tancredi, Giovanna; Gu, Xiu; Frisk Kockum, Anton; Krantz, Philip; Delsing, Per; Bylander, Jonas | Here we present our work towards characterizing these effects, and we compare schemes for automating the recalibration process on a device consisting of fixed-frequency transmon qubits with a tunable coupler. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

868 | Efficient cavity control with SNAP gates | Foesel, Thomas; Krastanov, Stefan; Jiang, Liang; Marquardt, Florian | In this talk, we present a practical scheme to address this problem. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

869 | Demonstrating a Continuous Set of Two-qubit Gates for Near-term Quantum Algorithms | Foxen, Brooks; Chiaro, Ben; McEwen, Matthew; Martinis, John | Quantum algorithms offer a dramatic speedup for computational problems in machine learning, material science, and chemistry. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

870 | Experimental implementation of universal nonadiabatic geometric quantum gates with a superconducting circuit | HUA, ZIYUE; Xu, Yuan; Chen, Tao; Pan, Xiaoxuan; Li, Xuegang; Han, Jiaxiu; Cai, Weizhou; Ma, Yuwei; Wang, Haiyan; Song, Yipu; Xue, Zhengyuan; Sun, Luyan | In this work, we experimentally realize a universal nonadiabatic geometric quantum gate set in a superconducting qubit chain. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

871 | Bounds on cross-resonance gate fidelity in an extended parameter regime | Pritchett, Emily; Kandala, Abhinav; McKay, David | As we reach the limit of fidelities achieved by control of our current devices, consideration of this larger parameter space will let us design devices with higher performance. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

872 | Superconducting qubit gates based on accelerated adiabatic evolution | Setiawan, Fnu; Groszkowski, Peter; Ribeiro, Hugo; Clerk, Aashish | We perform detailed theoretical studies and simulations exploring the performance of such gates in realistic superconducting qubit platforms. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

873 | Microwave-activated entangling gates in high coherence superconducting qubits | Nguyen, Long; Somoroff, Aaron; Ficheux, Quentin; Lin, Yen-Hsiang; Pechenezhskiy, Ivan; Chen, Yinqi; Nesterov, Konstantin; Vavilov, Maxim; Manucharyan, Vladimir | We report experimental progress on microwave-activated entangling gates with capacitively coupled fluxonium qubits. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

874 | Demonstration of entangling gate for all-to-all connected superconducting qubits | Lu, Marie; Ville, Jean-Loup; Schreppler, Sydney; Motzoi, Felix; Buchmann, Lukas; Siddiqi, Irfan | We report on the observed fidelity for a Mølmer-Sørensen-like interaction through the use of shared coplanar waveguide (CPW) resonators to couple multiple superconducting qubits. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

875 | Multi-qubit gate mediated by a shared microwave resonator: Error analysis | Ville, Jean-Loup; Lu, Marie; Schreppler, Sydney; Motzoi, Felix; Buchmann, Lukas; Siddiqi, Irfan | We discuss in this talk the different sources of errors currently limiting the fidelity of the gate, relative to the coherence of the driving fields and the lifetimes of the dressed qubits. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

876 | Fidelity Optimization of the Cross-resonance Gate on a Multi-qubit Quantum Processor | Naik, Ravi; Mitchell, Bradley; Hashim, Akel; Kreikebaum, John Mark; Siddiqi, Irfan | In this work, we benchmark the performance of the cross-resonance gate in a multi-qubit setting, and evaluate gate fidelity as a function of circuit and control parameters, such as qubit detuning, effective coupling rate, and control pulse shape. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

877 | A continuously tunable coupler for switching off adjacent qubit coupling in a superconducting circuit | Li, Xuegang; Cai, Tianqi; Wang, Zhiling; Pan, Xiaoxuan; Ma, Yuwei; Cai, Weizhou; Han, Jiaxiu; Han, Xiyue; Wu, Yukai; Zhang, Hongyi; Song, Yipu; Duan, Luming; Sun, Luyan | We achieve an average controlled-Z gate fidelity of 98.3%, characterized via quantum process tomography and dominantly limited by the system decoherence. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

878 | Cancellation of unwanted ZZ interactions by superconducting qubit engineering | Winik, Roni; Leroux, Catherine; Di Paolo, Agustin; Braumueller, Jochen; Kjaergaard, Morten; Vepsalainen, Antti; Kim, David; Yoder, Jonilyn; Melville, Alexander; Niedzielski, Bethany; Blais, Alexandre; Gustavsson, Simon; Oliver, William | We present a method to cancel the unwanted always-on ZZ interaction in transmon based qubit architectures by qubit engineering. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

879 | Implementation of a conditional-phase gate by using in-situ tunable ZZ-interactions | Herrmann, Johannes; Collodo, Michele; Andersen, Christian Kraglund; Remm, Ants; Lazar, Stefania; Chen, Liangyu; Lacroix, Nathan; Besse, Jean-Claude; Walter, Theo; Wallraff, Andreas; Eichler, Christopher | Here, we present an alternative approach using a tunable ZZ-interaction between two-qubits, mediated by a flux-tunable coupler element. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

880 | Two-qubit coupler with exponential suppression of virtual interactions | Leroux, Catherine; Di Paolo, Agustin; Blais, Alexandre | We present a superconducting two-qubit coupler where a tunable bus interacts with a driven mode such as to, on demand, exponentially suppress the qubit-qubit virtual interactions with respect to the amplitude of the external control field. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

881 | Suppression of Qubit Crosstalk between Transmons and Capacitively Shunted Flux Qubits : Part1, Experiment | Ku, Jaseung; Plourde, Britton; Hertzberg, Jared; Brink, Markus; McKay, David; Chow, Jerry; Xu, Xuexin; Ansari, Mohammad | In this talk, we will present experimental results from these measurements, including the ZZ crosstalk and two-qubit gate fidelity versus detuning between the two qubits. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

882 | Suppression of Qubit Crosstalk between Transmons and Capacitively Shunted Flux Qubits: Part 2, Theory | Xu, Xuexin; Ansari, Mohammad; Ku, Jaseung; Plourde, Britton; Hertzberg, Jared; Brink, Markus; McKay, David; Chow, Jerry | We compare two-qubit superconducting circuits composed of either different-species qubits or all-transmon qubits. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

883 | High fidelity encoded gate operations for composite superconducting qubit | Shim, Yun-Pil; Campbell, Daniel; Kannan, Bharath; Winik, Roni; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Orlando, Terry; Gustavsson, Simon; Oliver, William; Tahan, Charles | High fidelity encoded gate operations for composite superconducting qubit | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

884 | A multi-qubit gate for non-interacting qubits in circuit-QED using the Zeno effect | Mor, Chen; Koren, Boaz; Diringer, Asaf; Hacohen-Gourgy, Shay | We present the experimental results and discuss the fidelity and limitations of this gate. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

885 | Cross-resonance Dynamics with Tunable Transmon Qubits | Mitchell, Bradley; Naik, Ravi; Hashim, Akel; Kreikebaum, John Mark; Siddiqi, Irfan | We experimentally investigate the dynamics of the cross-resonance gate across a range of qubit detuning, intrinsic coupling strength, drive frequency, and compare our findings with the model. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

886 | Density Matrix Exponentiation on a Superconducting Quantum Processor (Part 1): Introduction and construction | Kjaergaard, Morten; Schwartz, Mollie; Greene, Amy; Samach, Gabriel; Bengtsson, Andreas; O’Keeffe, Michael; McNally, Chris; Sung, Youngkyu; Marvian, Milad; Krantz, Philip; Braumueller, Jochen; Winik, Roni; Kim, David; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Rosenberg, Danna; Obenland, Kevin; Orlando, Terry; Marvian, Iman; Gustavsson, Simon; Lloyd, Seth; Oliver, William | In Part 1 of this talk, we will introduce the DME algorithm, its uses, and our experimental implementation on a small quantum processor using a 99.7% fidelity CPHASE gate between two superconducting transmons. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

887 | Density Matrix Exponentiation on a Superconducting Quantum Processor (Part 2): Demonstration and Characterization | Schwartz, Mollie; Kjaergaard, Morten; Greene, Amy; Samach, Gabriel; Bengtsson, Andreas; O’Keeffe, Michael; McNally, Chris; Sung, Youngkyu; Marvian, Milad; Krantz, Philip; Braumueller, Jochen; Winik, Roni; Kim, David; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Rosenberg, Danna; Obenland, Kevin; Orlando, Terry; Marvian, Iman; Gustavsson, Simon; Lloyd, Seth; Oliver, William | In Part 2 of this talk, we benchmark an implementation of the DME algorithm in a two-qubit system. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

888 | Experimental considerations for zero noise extrapolation | Kandala, Abhinav; Temme, Kristan; Merkel, Seth; McKay, David; Magesan, Easwar; Gambetta, Jay | In particular, the zero-noise extrapolation technique was shown to extend the computational reach of a noisy superconducting processor. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

889 | Realizing giant artificial atoms in superconducting waveguide QED | Vadiraj, A.M.; Ask, Andreas; Nsanzineza, Ibrahim; Chang, Chung Wai; Frisk Kockum, Anton; Wilson, C.M. | For one qubit circuit, we demonstrate that we can enhance or suppress the relaxation rate of the 1-2 transition relative to the 0-1 transition by more than an order of magnitude. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

890 | Progress Towards Fast Dissipation-Induced Entanglement In Circuit-QED Using Parametric Interactions | Brown, Tristan; Doucet, Emery; Reiter, Florentin; Simmonds, Raymond; Aumentado, Jose; Ristè, Diego; Ranzani, Leonardo; Kamal, Archana | In this talk, I will discuss progress toward experimental realization of a parametrically-induced state stabilization scheme in circuit-QED architecture. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

891 | A novel bus design for a highly connected multi-qubit processor in 3D cQED architecture | Hazra, Sumeru; Bhattacharjee, Anirban; Salunkhe, Kishor; Chitransh, Sanskriti; Patankar, Meghan; Vijay, R | We will present a novel bus design to couple multiple qubits in 3D cQED with high inter-qubit connectivity and sufficient spatial separation to minimize cross-talk effects. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

892 | Waveguide-mediated Interactions Between Giant Superconducting Artificial Atoms | Kannan, Bharath; Ruckreigel, Max; Campbell, Daniel; Frisk Kockum, Anton; Braumueller, Jochen; Winik, Roni; Kjaergaard, Morten; Kim, David; Melville, Alexander; Niedzielski, Bethany; Yoder, Jonilyn; Orlando, Terry; Gustavsson, Simon; Oliver, William | We show that the coupling between the qubits and the waveguide can be strongly tuned with the qubit frequency. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

893 | Building and benchmarking diabatic entangling gates for frequency-tunable qubits, part I | Petukhov, Andre; Barends, Rami; Quintana, Chris; Chen, Yu; Smelyanskiy, Vadim | We present a non-adiabatic protocol for iSWAP-like gates with minimal leakage and duration close to the speed limit. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

894 | Building and benchmarking diabatic entangling gates for frequency-tunable qubits, part II | Barends, Rami; Quintana, Chris; Petukhov, Andre; Chen, Yu; Smelyanskiy, Vadim | We present the experimental implementation of a synchronization protocol for constructing gates that have minimal leakage and a duration close to the speed limit. | Session 56: Superconducting Qubits: Gates, Couplers and Crosstalk |

895 | Design and Fabrication of Impedance Matched Parametric Amplifiers for Quantum Applications | Grebel, Joel; Bienfait, Audrey; Chang, Hung-Shen; Chou, Ming-Han; Conner, Christopher; Dumur, Etienne; Peairs, Gregory; Povey, Rhys; Zhong, Youpeng; Cleland, Andrew | We will describe the circuit designs and fabrication process for on-chip impedance matched lumped-element JPAs ([2], [3]) operated in both three-wave and four-wave mixing modes. We will present data on the devices’ gain, saturation power, and bandwidth. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

896 | Josephson Array Mode Parametric Amplifier | Sivak, Volodymyr; Shankar, Shyam; Liu, Gangqiang; Aumentado, Jose; Devoret, Michel | We introduce a novel near-quantum-limited amplifier with a large tunable bandwidth and high dynamic range – the Josephson Array Mode Parametric Amplifier (JAMPA). | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

897 | Frequency Tunable Josephson Traveling Wave Parametric Amplifier with Nondegenerate Pump Phase Matching | Peng, Kaidong; Naghiloo, Mahdi; O’Brien, Kevin | Here we develop a resonator-free, dual-pump JTWPA with a reduced footprint, wider bandwidth, but comparable gain, dynamic range, and noise performance. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

898 | Minimal manifestation of Kerr-mediated frequency combs in superconducting circuits | Lu, Pinlei; Khan, Saeed; Chien, Tzu-Chiao; Cao, Xi; Tureci, Hakan; Hatridge, Michael | In this presentation, we present an experimental realization of a coherently driven, Kerr-mediated, microwave frequency comb. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

899 | Impedance-matched Josephson parametric amplifier using open stubs as shunt capacitance | Urade, Yoshiro; Zuo, Kun; Inomata, Kunihiro; Lin, Zhirong; Yamamoto, Tsuyoshi; Nakamura, Yasunobu | In this presentation, we show that open stubs (open-circuited transmission lines connected at one end) can be used as shunt capacitances for JPA resonators. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

900 | Four-port directional parametric amplifier | Joshi, Vidul; Liu, Gangqiang; Lingenfelter, Andrew; Shankar, Shyam; Devoret, Michel | We present the design and experimental progress towards realizing such a four-mode device which under appropriate drive conditions would act like an amplifier which has appreciable forward gain, has perfect isolation, is input- and output-matched and has an auxiliary port which acts as the cold load. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

901 | Pump-power-efficient 3-wave mixing Josephson parametric amplifier | Dai, Wei; Sivak, Volodymyr; Liu, Gangqiang; Shankar, Shyam; Devoret, Michel | To address this limitation, we apply on-chip impedance engineering to enable strong coupling of the off-resonance pump to a 3-wave-mixing JPA. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

902 | Optimizing Josephson-Ring-Modulator-based Josephson Parametric Amplifiers via full Hamiltonian control | Liu, Chenxu; Chien, Tzu-Chiao; Hatridge, Michael; Pekker, David | Here, we present a systematic study of the nonlinearities in JPAs, we show which nonlinearities limit the saturation power, and present a strategy for optimizing the circuit parameters for achieving the best possible JPA. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

903 | Dependence of Kerr nonlinearity on junction array size in Josephson parametric amplifiers | Liu, Gangqiang; Sivak, Volodymyr; Shankar, Shyam; Frunzio, Luigi; Devoret, Michel | We investigate the dependence of Kerr nonlinearity on the array size under realistic fabrication constraints. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

904 | A quantum state router based on parametrically driven photon exchange | Zhou, Chao; Lu, Pinlei; Praquin, Matthieu; Cao, Xi; Kaufman, Ryan; Mong, Roger; Pekker, David; Hatridge, Michael | We present a design that can realize long range couplings between qubits through a modular quantum router. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

905 | Superconducting Parametric Cavities as an “Optical” Quantum Computation Platform | Hung, Jimmy Shih-Chun; Chang, Chung Wai Sandbo; Vadiraj, A.M.; Nsanzineza, Ibrahim; Wilson, C.M. | Here, we propose and study the superconducting parametric cavity for optical quantum computation using microwave photons. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

906 | In-cavity parametric amplification for qubit readout in 3D circuit QED architecture | Wang, Zhixin; Sivak, Volodymyr; Mundhada, Shantanu; Shankar, Shyam; Devoret, Michel | Here we introduce a design that uses two coupled transmon artificial atoms housed in a 3D readout cavity/waveguide to perform quantum-limited amplification within the circuit QED module. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

907 | Amplification with an array of lumped Josephson Parametric Converters | Lanes, Olivia; Chien, Tzu-Chiao; Liu, Chenxu; Metelmann, Anja; Pekker, David; Hatridge, Michael | We have recently shown that when extremely strong, carefully imbalanced gain and conversion processes (GCI) are combined between a pair of modes, we produce an amplifier that has broadband, bi-directional gain in transmission and is matched at both ports. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

908 | Experimental violation of the standard quantum limit for parametric amplification of broadband signals | Renger, Michael; Fedorov, Kirill; Pogorzalek, Stefan; Chen, Qi-Ming; Nojiri, Yuki; Partanen, Matti; Marx, Achim; Deppe, Frank; Gross, Rudolf | We demonstrate that the SQL does not hold for broadband input signals and experimentally find η = 70% with an amplification chain consisting of a JPA and a cryogenic HEMT amplifier. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

909 | Nonreciprocal amplification via Hamiltonian Engineering | Chien, Tzu-Chiao; Liu, Chenxu; Lu, Pinlei; Lanes, Olivia; Cao, Xi; Kaufman, Ryan; Pekker, David; Hatridge, Michael | We avoid the use of hybrids by integrating the LJPC and superconducting bandpass filters on a single chip. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

910 | Boardband Tunable Phase Shifter for Microwaves | Zhang, Jinli; Mottonen, Mikko; Li, Tianyi; Kokkoniemi, Roope; Tan, Kuan; Yan, Chengyu; Liu, Wei | Recently, we introduced a magnetic-flux-tunable phase shifter for propagating microwaves based on three equidistant SQUIDs operating at a single frequency. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

911 | Phase noise of a Josephson parametric oscillator | Lakshmi Bhai, Gopika; Shirai, Shotaro; Mukai, Hiroto; Zhou, Yu; Sudhir, Vivishek; Tsai, Jaw-Shen | Here we present the results on the experimental study of the phase diffusion properties of such an oscillator by measuring the phase noise spectrum. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

912 | A Josephson Maser Via Three-Wave Coupling | Mucci, Maria; Cao, Xi; Liu, Chenxu; Kaufman, Ryan; Pekker, David; Hatridge, Michael | Instead of a three-level atom, we present a joint system of a single qubit and a three-wave mixing resonator, realized in a transmon and SNAIL (Superconducting Nonlinear Asymmetric Inductive eLement), respectively. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

913 | Engineered frequency combs in a multimode Josephson network | Khan, Saeed; Tureci, Hakan | We investigate the dynamics of a microwave-driven Josephson junction capacitively coupled to an arbitrary multimode linear network. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

914 | Theory of an on-chip Josephson quantum micromaser | Pekker, David; Liu, Chenxu; Mucci, Maria; Cao, Xi; Hatridge, Michael | To solve this problem, we explore the feasibility of building a Josephson micromaser powered by tunable superconducting transmon qubit(s) (which serve as an artificial three-level atom). | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

915 | Microwave Isolation through Adiabatic Mode Conversion in Superconducting Coupled Transmission Lines | Naghiloo, Mahdi; Peng, Kaidong; Ye, Yufeng; O’Brien, Kevin | We report on progress toward implementing this device. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

916 | Design of a Josephson Travelling Wave Photon Detector | Ye, Yufeng; Peng, Kaidong; Naghiloo, Mahdi; O’Brien, Kevin | Here, we investigate a new design for the Josephson travelling wave photon detector[1,2], a circuit QED based detector which promises high fidelity, non-destructive, and broadband detection of microwave photons. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

917 | Experimental studies of flux solitons in reversible logic gates | Yu, Liuqi; Wustmann, Waltraut; Osborn, Kevin | Here we design and measure 1-bit gates implemented in superconducting circuits. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

918 | Drive-induced renormalization of Kerr nonlinearity in superconducting circuits | Petrescu, Alexandru; Royer, Baptiste; Blais, Alexandre | We propose a perturbative expansion based on unitary transformations to calculate drive-induced corrections to Kerr interactions, with possible applications to current experiments. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

919 | Observation of the AC Stark shift and idler-resonance in two-tone measurements of a Josephson resonator | Fani Sani, Fatemeh; Bothner, Daniel; Rodrigues, Ines; Steele, Gary | We report on the behaviour of a nonlinear Josephson cavity driven by two microwave signals. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

920 | Millimeter-Wave Four-Wave Mixing via Kinetic Inductance for Quantum Devices | Anferov, Alexander; Suleymanzade, Aziza; Oriani, Andrew; Simon, Jonathan; Schuster, David | We report on the performance of low-loss planar resonators around 100 GHz, patterned on high kinetic inductance thin films of niobium nitride grown by atomic layer deposition. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

921 | Towards the development of a microwave to millimeter-wave quantum frequency converter | Multani, Kevin; Stokowski, Hubert; Witmer, Jeremy; Jiang, Wentao; Patel, Rishi; Lee, Nathan; Pechal, Marek; Snively, Emma; Welander, Paul; Nanni, Emilio; Safavi-Naeini, Amir | This talk will outline our experimental approach to a microwave-mmWave conversion scheme, where high bandwidth and high rate interconnects can be created at the laboratory scale. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

922 | Fractional harmonic instabilities in a quantum driven non-linear oscillator | Venkatraman, Jayameenakshi; Xiao, Xu; Zhang, Yaxing; Mirrahimi, Mazyar; Frunzio, Luigi; Devoret, Michel | In this work, we provide a map in parameter space of the instabilities that are created when the ratio of the drive and the mode transition frequencies coincide with rational numbers. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

923 | Dynamical Lamb effect in a superconducting circuit | Amico, Mirko; Berman, Oleg; Kezerashvili, Roman | We show that by using a superconducting circuit which allows one to switch between longitudinal and transverse coupling of a qubit to a resonator, it is possible to observe the dynamical Lamb effect. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

924 | Time-Domain Grating with a Periodically Driven Qutrit | Han, Yingying; Zhang, Wenxian; Nori, Franco; You, Jianqiang; Luo, Xiaoqing; Li, Tiefu | We report the experimental realization of time-domain grating using a superconducting qutrit in periodically modulated probe and control fields via two schemes: simultaneous modulation and complementary modulation. | Session 57: Superconducting Qubits: Josephson Junction-based Amplifiers and Parametric Devices |

925 | PAMBE grown NbTiN-AlN-NbTiN Josephson junction heterostructures for superconducting quantum circuits | Richardson, Christopher; Thomas, Austin; Alexander, Ashish; Weddle, Christopher; Kramer, Alan; Olszta, Matthew; Arey, Bruce | Using a structure first approach to design optimization, the structural, surface topology, bonding, and interface characteristics will be described. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

926 | Temperature Dependence of Relaxation-Time Fluctuations in Transmon Qubits | Dutta, Sudeep; Li, Kungang; Zhang, Rui; Poppert, Dylan; Keshvari, Shahriar; Lobb, Christopher; Wellstood, Frederick | Comparing with shorter lived transmons, we find that the size of the fluctuations in T 1 appears to scale with T 1. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

927 | Engineering Dynamical Sweet Spots to Protect Qubits from 1/f Noise | Huang, Ziwen; Gyenis, Andras; Mundada, Pranav; Schuster, David; Houck, Andrew; Koch, Jens | We present a protocol for engineering dynamical sweet spots protecting against 1/f noise, using a periodic drive. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

928 | Investigating the mechanisms of charge-parity switching in offset-charge-sensitive transmons | Diamond, Spencer; Serniak, Kyle; Hays, Max; Fatemi, Valla; Frunzio, Luigi; Schoelkopf, Robert; Catelani, Gianluigi; Houzet, Manuel; Glazman, Leonid; Devoret, Michel | Here, we will present experimental results demonstrating that adding flux-tunability to our device can further distinguish between these charge-parity switch-induced decoherence mechanisms. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

929 | Effect of external high-energy radiation on coherence of superconducting qubits | Vepsalainen, Antti; Karamlou, Amir; Orrell, John; Dogra, Akshunna; Vasconcelos, Fransisca; Loer, Ben; Niedzielski, Bethany; Melville, Alexander; Kim, David; Schwartz, Mollie; Yoder, Jonilyn; VanDevender, Brent; Gustavsson, Simon; Oliver, William | We propose that in addition to this effect, gamma-rays from radioactive decays in the environment are also a significant source of quasi-particle breaking radiation. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

930 | Synchrotron X-ray studies of superconducting qubit materials | Jarrige, Ignace; Premkumar, Anjali; Weiland, Conan; Berthold, Jack; Place, Alexander; Waluyo, Ira; Hunt, Adrian; Kiss, Andrew; Chu, Yong; Bisogni, Valentina; Pelliciari, Jonathan; Rumaiz, Abdul; Miller, Mike; Russo, Paula; Schuster, David; Houck, Andrew | Here, we report on the combined use of synchrotron X-ray scattering and spectroscopic tools to probe the surface electronic and bulk structural properties of Nb thin films deposited on sapphire, which emulate qubit capacitor pads. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

931 | Highly uniform submicron junction arrays and applications to next generation photodetectors | Kreikebaum, John Mark; O’Brien, Kevin; Royer, Baptiste; Grimsmo, Arne; Blais, Alexandre; Siddiqi, Irfan | Analyzing junction array resistance distributions from many wafers, we have identified several key processing variables to improve uniformity. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

932 | Loss Characterization in Superconducting Resonators | Melville, Alexander; Calusine, Greg; Woods, Wayne; Serniak, Kyle; Golden, Evan; Sevi, Arjan; Yoder, Jonilyn; Oliver, William | In this talk, we characterize the change in overall quality factor and dielectric-specific loss tangent arising from specific changes to the fabrication process. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

933 | Modeling geometric dependence of dielectric losses in superconducting coplanar-waveguide resonators | Lahtinen, Valtteri; Mottonen, Mikko | Combining the simulations with measured two-level-system-limited Q factors of CPW resonators, we solve an inverse problem to find optimal model parameters producing these values. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

934 | Reducing dephasing for flux control of superconducting qubits | Didier, Nicolas | We consider how flux pulses can protect a tunable qubit from slow flux noise for a range of frequencies in the tunability band. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

935 | Characterizing noise for capacitively-shunted flux qubits | Tripathi, Vinay; Khezri, Mostafa; Chen, Huo; Lidar, Daniel | We report a joint theoretical-experimental study of 1/f noise in CSFQs using Macroscopic Resonance Tunneling (MRT). | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

936 | Microwave loss of van der Waals dielectrics in the low-temperature, single-photon regime | Wang, Joel; Yamoah, Megan; Li, Qing; Boettcher, Charlotte; Kannan, Bharath; Kim, David; Yoder, Jonilyn; Watanabe, Kenji; Taniguchi, Takashi; Orlando, Terry; Gustavsson, Simon; Jarillo-Herrero, Pablo; Oliver, William | Researches have shown the loss occurs in the bulk of dielectrics as well as of the many interfaces of circuit elements. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

937 | Loss Mechanisms in Superconducting Quantum Transmission Line Metamaterials | Tai, Tamin; Cai, Jingnan; Anlage, Steven | Loss Mechanisms in Superconducting Quantum Transmission Line Metamaterials | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

938 | Over-100µs tunable planar transmons: epitaxial Josephson Junctions and design optimization | Pishchimova, Anastasiya; Moskalev, Dmitriy; Matanin, Aleksei; Dobronosova, Alina; Ezenkova, Daria; Malevannaya, Elizaveta; Besedin, Ilya; Sorokina, Olga; Ganieva, Lucia; Michael, Andronic; Echeistov, Vladimir; Zverev, Alexander; Yakovlev, Dmitriy; Rodionov, Ilya | From the other hand, we propose novel superconducting qubits fabrication technique based on Josephson junction epitaxial growth with inorganic masks. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

939 | Superconducting qubit devices: fabrication suite | Chan, Kok Wai; Li, Tianyi; Liu, Wei; Heinsoo, Johannes; Sevriuk, Vasilii; Ockeloen-Korppi, Caspar; Tuorila, Jani; Hassel, Juha; Vartiainen, Juha; Tan, Kuan; Goetz, Jan; Mottonen, Mikko | We present the fabricated devices and results achieved to date, which includes resonators with high quality factors, > 1e6, long qubit lifetime > 0.02 ms and 3D integration techniques such as airbridges. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

940 | NbN-based superconducting qubit on Si substrate | Kim, Sunmi; Fuse, Tomoko; Yoshihara, Fumiki; Qiu, Wei; Yamashita, Taro; Ao, Ziqiao; Semba, Kouichi; Terai, Hirotaka | Early studies of superconducting qubits using epitaxially grown nitride JJs showed significant potential, but the qubit energy relaxation time was limited due to dielectric loss from the MgO substrate. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

941 | Flux qubits fabricated using a high-coherence transmon process | Chistolini, Trevor; Livingston, William; Mitchell, Bradley; Siddiqi, Irfan | We now apply these advances in processing to look back upon flux qubits, and we present an 8-qubit ring of alternating flux qubits and tunable transmons, with coupling between nearest neighbors. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

942 | Fabrication and characterization of compact vacuum gap transmon qubits | Zemlicka, Martin; Peruzzo, Matilda; Hassani, Farid; Barzanjeh, Shabir; Redchenko, Elena; Trioni, Andrea; Fink, Johannes | Our goal is the development of a compact low-loss transmon qubit by minimizing the electric field participation ratio of metal-dielectric and dielectric-air interfaces. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

943 | Characterization of Al-based Airbridges for Superconducting Microwave Devices. | Najafi Jabdaraghi, Robab; Grönberg, Leif; Vesterinen, Visa; Prunnila, Mika | Here, we demonstrate our latest development of Al airbridges in conjunction with Nb CPWs. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

944 | Epitaxial GaAs Loss Measurements and the Merged Element Transmon | McRae, Corey Rae; McFadden, Anthony; Zhao, Ruichen; Wang, Haozhi; Park, Sungoh; Long, Junling; Palmstrom, Chris; Pappas, David | In this work, we use dielectric loss extraction methods to accurately measure the TLS loss for Al/GaAs/Al trilayers. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

945 | Frequency Fluctuations in Tunable Superconducting Microwave Cavities | Brock, Benjamin; Blencowe, Miles; Rimberg, Alexander | We present a model for measurements of the scattering matrix elements of tunable microwave cavities in the presence of resonant frequency fluctuations induced by fluctuations in the tuning parameter. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

946 | Investigation of surface induced loss mechanisms in high-quality superconducting Nb resonators | Verjauw, Jeroen; Mongillo, Massimo; Potocnik, Anton; Acharya, Rohith; Pacco, Antoine; Ivanov, Tsvetan; Wan, Danny; Souriau, Laurent; Jussot, Julien; Thiam, Arame; Swerts, Johan; Piao, Xiaoyu; Couet, Sebastien; Govoreanu, Bogdan; Radu, Iuliana; Heyns, Marc | Reducing microwave loss contributions from these interfaces by proper surface treatments is key to push the device performance forward. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

947 | Flux Noise and Spin Dynamics of Multiple Interacting Adsorbates on Superconducting Qubits | Ray, Keith; Rosen, Yaniv; DuBois, Jonathan; Lordi, Vincenzo | To better understand the spin dynamics of these fluctuating adsorbates we have extended our model for interacting adsorbed paramagnetic O 2 molecules to include other species adsorbed from the device operation atmosphere, including water at different coverages. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

948 | Positive- and negative-frequency noise from an ensemble of two-level fluctuators | You, Xinyuan; Clerk, Aashish; Koch, Jens | We extend the analysis beyond this limit, and derive results explicitly obeying the fluctuation–dissipation theorem. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

949 | Random two-level defects in polycrystalline and amorphous alumina | Hung, Chih-Chiao; Osborn, Kevin; Forouzani, Neda; Sarabi, Bahman | We extend a characterization technique to, for the first time, study TLSs in two states of the same material: amorphous and polycrystalline alumina. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

950 | Coplanar silicon/aluminum resonators with internal quality factor above 2M: fabrication | Gabidullin, Aidar; Dobronosova, Alina; Ivanov, Anton; Ganieva, Lucia; Moskalev, Dmitriy; Michael, Andronic; Smirnov, Nikita; Baklykov, Dmitriy; Sorokina, Olga; Fedorov, Gleb; Rodionov, Ilya | Here we describe the fabrication and measurement of superconducting coplanar waveguide microwave resonators on silicon substrates with internal quality factors over 2 millions at low powers, corresponding to single-photon regime. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

951 | Long Relaxation Times of a C-shunt Flux Qubit Coupled to a 3D Cavity | Abdurakhimov, Leonid; Mahboob, Imran; Toida, Hiraku; Kakuyanagi, Kousuke; Saito, Shiro | We present measurements of relaxation times of a capacitively shunted flux qubit embedded in a 3D microwave cavity. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

952 | Coplanar silicon/aluminum resonators with internal quality factor above 2M: measurements | Ivanov, Anton; Polozov, Viktor; Malevannaya, Elizaveta; Matanin, Aleksei; Samoylov, Andrey; Echeistov, Vladimir; Zverev, Alexander; Michael, Andronic; Gabidullin, Aidar; Fedorov, Gleb; Rodionov, Ilya | In this work, we focused on sample holders design and materials simulations, verified by superconducting resonators quality factor and qubits lifetime cryogenic measurements. | Session 58: Superconducting Qubits: Materials, Fabrication and Coherence |

953 | Ground state of a circuit QED system in the deep-strong-coupling regime coupled to an environment | Shitara, Tomohiro; Bamba, Motoaki; Yoshihara, Fumiki; Fuse, Tomoko; Semba, Kouichi; Koshino, Kazuki | We investigate theoretically how the ground state of a qubit-resonator system in the deep-strong coupling regime is modified by the coupling to an environment. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

954 | Time-domain measurements of an ultra-strongly coupled qubit-resonator circuit | Fuse, Tomoko; Yoshihara, Fumiki; Ashhab, Sahel; Kakuyanagi, Kousuke; Saito, Shiro; Semba, Kouichi | In this work, we have measured the coherence properties of an ultra-strongly coupled flux qubit-resonator circuit by driving the qubit while probing the resonator transition, which is also flux-bias dependent due to its very strong coupling to the qubit. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

955 | Rabi model in the dispersive regime | Mueller, Clemens | Here we present our results on the dispersive regime of the Rabi model, without taking the rotating wave approximation of the underlying Hamiltonian. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

956 | Conical intersections and Berry phase in deep-strongly coupled superconducting qubit-resonator system | Semba, Kouichi; Ashhab, Sahel | Here, we propose an experimental scheme to observe conical intersections in the energy landscape and the Berry phase in ultra- or deep-strongly coupled qubit-resonator systems. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

957 | Quantum impurity physics meets circuit QED: observation of finite lifetime photons | Kuzmin, Roman; Grabon, Nicholas; Mehta, Nitish Jitendrakumar; Goldstein, Moshe; Manucharyan, Vladimir | We report a new regime of quantum electrodynamics (QED) where a single photon acquires a finite lifetime due to spontaneous decay to many lower-frequency photons. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

958 | Cavity-free circuit quantum electrodynamics: interfacing a high-coherence qubit with propagating photons | Lin, Yen-Hsiang; Xiong, Haonan; Cottet, Nathanael; Nguyen, Long; Mencia, Ray; Somoroff, Aaron; Manucharyan, Vladimir | We report experiments with a fluxonium artificial atom directly connected to a 1D transmission line. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

959 | Experimental Demonstration of Quantum Error Detection with a Small Surface Code | Andersen, Christian Kraglund; Remm, Ants; Lazar, Stefania; Lacroix, Nathan; Krinner, Sebastian; Norris, Graham; Gabureac, Mihai; Eichler, Christopher; Wallraff, Andreas | We present measurements of all three stabilizers with high fidelity and repeated detection of errors on the data qubits using the stabilizer readout. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

960 | Evaluation of the Performance of a 7-Qubit Surface Code | Remm, Ants; Andersen, Christian Kraglund; Lazar, Stefania; Lacroix, Nathan; Krinner, Sebastian; Norris, Graham; Gabureac, Mihai; Eichler, Christopher; Wallraff, Andreas | In this talk we analyse the physical error mechanisms of a seven-qubit superconducting quantum device on which we implement the elementary operations required for a surface code. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

961 | Real-time decoding of repeated stabilizer measurements in a bit-flip code | Ristè, Diego; Govia, Luke; Donovan, Brian; Fallek, Spencer; Kalfus, William; Takita, Maika; Corcoles, Antonio; Brink, Markus; Bronn, Nicholas; Chow, Jerry | Here we present a classical control architecture for the fast extraction of errors based on multiple rounds of stabilizer measurements, and subsequent optional correction. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

962 | Real-time Quantum Error Correction for a Surface-Code Logical Qubit | Moreira, Miguel; Tarasinski, Brian; Gloudemans, Jordy; Ostroukh, Viacheslav; Vlothuizen, Wouter; DiCarlo, Leonardo | We present a control architecture for surface code with a tightly-coupled real-time quantum error decoder. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

963 | Continuous Parity Measurement and Error Correction | Livingston, William; Blok, Machiel; Atalaya, Juan; Mohseninia, Razieh; Yang, Jing; Jordan, Andrew; Dressel, Justin; Siddiqi, Irfan | Using a chip with three qubits and connecting each of two pairs to a parity readout resonator, we implement the two parity measurements needed to perform the conventional three-qubit bit-flip code. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

964 | Topological and subsystem codes on low-degree graphs with flag qubits | Zhu, Guanyu; Chamberland, Christopher; Yoder, Theodore; Hertzberg, Jared; Cross, Andrew | In this work we introduce two code families, the heavy hexagon code and heavy square code. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

965 | Detection and mitigation of leakage in simulations of a transmon implementation of the surface code, Part 1: Characterization of leakage effects in a realistic error model | Battistel, Francesco; Varbanov, Boris; Tarasinski, Brian; Ostroukh, Viacheslav; O’Brien, Thomas; DiCarlo, Leonardo; Terhal, Barbara | In this work, we employ realistic full-trajectory simulations of the CZ gate in a transmon system (the dominant source of leakage in this system). | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

966 | Detection and mitigation of leakage in simulations of a transmon implementation of the surface code, Part 2: Scalable Hidden Markov models for the identification of leakage | Varbanov, Boris; Battistel, Francesco; Tarasinski, Brian; Ostroukh, Viacheslav; O’Brien, Thomas; Terhal, Barbara; DiCarlo, Leonardo | We explore the effects of leakage on the performance of the distance-3 surface code Surface-17 by performing density-matrix simulations, employing realistic error models for transmon qubits in a circuit QED processor. | Session 59: Superconducting Qubits: QEC and Ultrastrong Coupling |

967 | Bifurcating entanglement-renormalization group flows of fracton stabilizer models | Dua, Arpit; Sarkar, Pratyush; Williamson, Dominic; Cheng, Meng | We investigate the entanglement-renormalization group flows of translation-invariant topological stabilizer models in three dimensions. | Session 60: Topological Quantum Computing |

968 | Quantum electrodynamics in a topological metamaterial: Part 1 | Kim, Eun Jong; Zhang, Xueyue; Sipahigil, Alp; Ferreira, Vinicius; Banker, Jash; Mirhosseini, Mohammad; Painter, Oskar | We discuss the implementation of the topological waveguide with superconducting metamaterials. | Session 60: Topological Quantum Computing |

969 | Quantum electrodynamics in a topological metamaterial: Part 2 | Zhang, Xueyue; Kim, Eun Jong; Sipahigil, Alp; Ferreira, Vinicius; Banker, Jash; Mirhosseini, Mohammad; Painter, Oskar | Here, we study superconducting qubits coupled to a microwave metamaterial waveguide which is a photonic analog of the Su-Schrieffer-Heeger (SSH) model [Sci. | Session 60: Topological Quantum Computing |

970 | Transition from 2D to 1D topological superconductivity in a triangular island of p-wave superconductor | Winblad, Aidan; Chen, Hua | Using the mean-field Bogoliubov-de Gennes theory, we solve a tight-binding model with Rashba spin-orbit coupling, out-of-plane Zeeman field, and s-wave pairing on an equilateral triangle, which hosts chiral Majorana edge modes. | Session 60: Topological Quantum Computing |

971 | Time-resolved electrical detection of chiral edge vortex braiding | Adagideli, Inanc; Hassler, Fabian; Grabsch, Aurelien; Pacholski, Michal; Beenakker, Carlo | We calculate the time dependent current profile for the fusion process, which consists of $\bm{\pm e/2}$ charge pulses that flip sign if the world lines of the vortices are braided prior to the fusion. | Session 60: Topological Quantum Computing |

972 | Braiding of Majorana Fermions in a Cavity | Trif, Mircea; Simon, Pascal | We show theoretically that the π/4 phase associated with the braiding of MBS, as well as the parity of the ground state are imprinted into the photonic field of the cavity, which can be detected by dispersive readout techniques [1]. | Session 60: Topological Quantum Computing |

973 | Braiding Majorana Fermions and Creating Quantum Logic Gates with Vortices on a Periodic Pinning Structure | Ma, Xiaoyu; Reichhardt, Cynthia; Reichhardt, Charles | We show how vortices that support Majorana fermions when placed on a periodic pinning array can be used for vortex exchange and independent braiding by performing a series of specific moves with a probe tip. | Session 60: Topological Quantum Computing |

974 | Towards practical self-correction with augmented Majorana stabilizer codes | Plugge, Stephan; Franz, Marcel; Raussendorf, Robert; Affleck, Ian | In this talk, I will discuss MSCs and their extensions affording improved error-correction, towards the goal of thermally stable quantum memories in 2D. | Session 60: Topological Quantum Computing |

975 | Optimizing Clifford gate generation for measurement-only topological quantum computation with Majorana zero modes | Tran, Alan; Bocharov, Alex; Bauer, Bela; Bonderson, Parsa | We examine this problem for a measurement-only topological quantum computer based on Majorana zero modes (MZMs), where gates are performed through sequences of measurements. | Session 60: Topological Quantum Computing |

976 | Computational universality of symmetry-protected topologically ordered cluster phases on 2D Archimedean lattices | Daniel, Austin; Alexander, Rafael; Miyake, Akimasa | Motivated by this, we analyze the computational capability of SPTO cluster phases on all vertex-translative 2D Archimedean lattices. | Session 60: Topological Quantum Computing |

977 | Parafermions and Z3 Charge-Flux attachment | Rao, Peng; Shenoy, Vijay; Sodemann, Inti | We discuss an extension of these ideas to the case of a Z N toric which allows a bosonization of anyons with more general statitistical angles. | Session 60: Topological Quantum Computing |

978 | Fun with fractons | Williamson, Dominic | I will describe some recent efforts to tame the vast array of models with the goal of a systematic construction and classification of all topological phases of matter in three spatial dimensions. | Session 60: Topological Quantum Computing |