PRX quantum : a Physical Review journal最新文献

Nondegenerate Josephson mixers with enhanced bandwidth and saturation power for quantum signal amplification and transduction 具有增强带宽和饱和功率的非简并约瑟夫森混频器用于量子信号放大和转导

PRX quantum : a Physical Review journal Pub Date : 2026-04-22 DOI: 10.1103/s1s8-r7y2

Anonymous

引用次数: 0

Erasure conversion in integer fluxonium qubits 整型氟量子比特的擦除转换

PRX quantum : a Physical Review journal Pub Date : 2026-03-17 DOI: 10.1103/jszm-48h7

Anonymous

引用次数: 0

Resource-Efficient Cross-Platform Verification with Modular Superconducting Devices 模块化超导器件的资源高效跨平台验证

PRX quantum : a Physical Review journal Pub Date : 2025-11-03 DOI: 10.1103/czph-xpzs

Kieran Dalton, Johannes Knörzer, Finn Hoehne, Yookyung Song, Alexander Flasby, Dante Colao Zanuz, Mohsen Bahrami Panah, Ilya S. Besedin, Jean-Claude Besse, Andreas Wallraff

{"title":"Resource-Efficient Cross-Platform Verification with Modular Superconducting Devices","authors":"Kieran Dalton, Johannes Knörzer, Finn Hoehne, Yookyung Song, Alexander Flasby, Dante Colao Zanuz, Mohsen Bahrami Panah, Ilya S. Besedin, Jean-Claude Besse, Andreas Wallraff","doi":"10.1103/czph-xpzs","DOIUrl":"https://doi.org/10.1103/czph-xpzs","url":null,"abstract":"Large-scale quantum computers are expected to benefit from modular architectures. Validating the capabilities of modular devices requires benchmarking strategies that assess performance within and between modules. In this work, we evaluate cross-platform verification protocols, which are critical for quantifying how accurately different modules prepare the same quantum state—a key requirement for modular scalability and system-wide consistency. We demonstrate these algorithms using a six-qubit flip-chip superconducting quantum device consisting of two 3-qubit modules on a single carrier chip, with connectivity for intra- and intermodule entanglement. We examine how the resource requirements of protocols relying solely on classical communication between modules scale exponentially with qubit number, and demonstrate that introducing an intermodule two-qubit gate enables subexponential scaling in cross-platform verification. This approach reduces the number of repetitions required by a factor of 4 for three-qubit states, with greater reductions projected for larger and higher-fidelity devices.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147382135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Realizing a Continuous Set of Two-Qubit Gates Parameterized by an Idle Time 用空闲时间参数化连续双量子位门的实现

PRX quantum : a Physical Review journal Pub Date : 2025-08-04 DOI: 10.1103/h7cv-xgw2

Colin Scarato, Kilian Hanke, Ants Remm, Stefania Lazăr, Nathan Lacroix, Dante Colao Zanuz, Alexander Flasby, Andreas Wallraff, Christoph Hellings

{"title":"Realizing a Continuous Set of Two-Qubit Gates Parameterized by an Idle Time","authors":"Colin Scarato, Kilian Hanke, Ants Remm, Stefania Lazăr, Nathan Lacroix, Dante Colao Zanuz, Alexander Flasby, Andreas Wallraff, Christoph Hellings","doi":"10.1103/h7cv-xgw2","DOIUrl":"https://doi.org/10.1103/h7cv-xgw2","url":null,"abstract":"Continuous gate sets are a key ingredient for near-term quantum algorithms. Here, we demonstrate a hardware-efficient, continuous set of controlled arbitrary-phase ( <a:math xmlns:a=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"> <a:msub> <a:mrow> <a:mstyle mathsize=\"0.85em\"> <a:mi>CZ</a:mi> </a:mstyle> </a:mrow> <a:mi>θ</a:mi> </a:msub> </a:math> ) gates acting on flux-tunable transmon qubits. This implementation is robust to control pulse distortions on time scales longer than the duration of the gate, making it suitable for deep quantum circuits. Our calibration procedure makes it possible to parameterize the continuous gate set with a single control parameter, the idle time between the two rectangular halves of the net-zero control pulse. For calibration and characterization, we develop a leakage measurement based on coherent amplification, and a new cycle design for cross-entropy benchmarking. We demonstrate gate errors of <d:math xmlns:d=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"> <d:mrow> <d:mn>0.7</d:mn> </d:mrow> <d:mrow> <d:mi mathvariant=\"normal\">%</d:mi> </d:mrow> </d:math> and leakage of <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"> <g:mn>4</g:mn> <g:mo>×</g:mo> <g:msup> <g:mn>10</g:mn> <g:mrow> <g:mo>−</g:mo> <g:mn>4</g:mn> </g:mrow> </g:msup> </g:math> across the entire gate set. This native gate set has the potential to reduce the depth and improve the performance of near-term quantum algorithms compared to decompositions into <i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"> <i:msub> <i:mrow> <i:mstyle mathsize=\"0.85em\"> <i:mi>CZ</i:mi> </i:mstyle> </i:mrow> <i:mi>π</i:mi> </i:msub> </i:math> gates and single-qubit gates. Moreover, we expect the calibration and benchmarking methods to find further possible applications.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147883595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Quasiparticle Poisoning of Superconducting Qubits with Active Gamma Irradiation 有源伽马辐射下超导量子比特的准粒子中毒

PRX quantum : a Physical Review journal Pub Date : 2025-07-14 DOI: 10.1103/2lyd-8swv

C.P. Larson, E. Yelton, Kenneth Dodge, Koichi Okubo, J. Batarekh, Vito Iaia, Noah Kurinsky, B. L. T. Plourde

{"title":"Quasiparticle Poisoning of Superconducting Qubits with Active Gamma Irradiation","authors":"C.P. Larson, E. Yelton, Kenneth Dodge, Koichi Okubo, J. Batarekh, Vito Iaia, Noah Kurinsky, B. L. T. Plourde","doi":"10.1103/2lyd-8swv","DOIUrl":"https://doi.org/10.1103/2lyd-8swv","url":null,"abstract":"When a high-energy particle, such as a <a:math xmlns:a=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><a:mi>γ</a:mi></a:math> ray or muon, impacts the substrate of a superconducting qubit chip, large numbers of electron-hole pairs and phonons are created. The ensuing dynamics of the electrons and holes changes the local offset-charge environment for qubits near the impact site. The phonons that are produced have energy above the superconducting gap in the films that compose the qubits, leading to quasiparticle excitations above the superconducting ground state when the phonons impinge on the qubit electrodes. An elevated density of quasiparticles degrades qubit coherence, leading to errors in qubit arrays. Because these pair-breaking phonons spread throughout much of the chip, the errors can be correlated across a large portion of the array, posing a significant challenge for quantum error correction. In order to study the dynamics of <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mi>γ</c:mi></c:math>-ray impacts on superconducting qubit arrays, we use a <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:mi>γ</e:mi></e:math>-ray source outside the dilution refrigerator to controllably irradiate our devices. By using charge-sensitive transmon qubits, we can measure both the offset-charge shifts and quasiparticle poisoning due to the <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:mi>γ</g:mi></g:math> irradiation at different doses. We study correlations between offset-charge shifts and quasiparticle poisoning for different qubits in the array and compare these with numerical modeling of charge and phonon dynamics following a <i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><i:mi>γ</i:mi></i:math>-ray impact. We thus characterize the poisoning footprint of these impacts and quantify the performance of structures for mitigating phonon-mediated quasiparticle poisoning.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147894174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Linear Quantum Coupler for Clean Bosonic Control 用于清洁玻色子控制的线性量子耦合器

PRX quantum : a Physical Review journal Pub Date : 2025-06-17 DOI: 10.1103/7rnm-rxhh

Aniket Maiti, John W.O. Garmon, Yao Lu, Alessandro Miano, Luigi Frunzio, Robert J. Schoelkopf

{"title":"Linear Quantum Coupler for Clean Bosonic Control","authors":"Aniket Maiti, John W.O. Garmon, Yao Lu, Alessandro Miano, Luigi Frunzio, Robert J. Schoelkopf","doi":"10.1103/7rnm-rxhh","DOIUrl":"https://doi.org/10.1103/7rnm-rxhh","url":null,"abstract":"Quantum computing with superconducting circuits relies on high-fidelity driven nonlinear processes. An ideal quantum nonlinearity would selectively activate desired coherent processes at high strength, without activating parasitic mixing products or introducing additional decoherence. The wide bandwidth of the Josephson nonlinearity makes this difficult, with undesired drive-induced transitions and decoherence limiting qubit readout, gates, couplers, and amplifiers. Significant strides have recently been made into building better “quantum mixers,” with promise being shown by Kerr-free three-wave mixers that suppress driven frequency shifts, and balanced quantum mixers that explicitly forbid a significant fraction of parasitic processes. We propose a novel mixer that combines both these strengths, with engineered selection rules that make it essentially linear (not just Kerr-free) when idle, and activate clean parametric processes even when driven at high strength. Furthermore, its ideal Hamiltonian is simple to analyze analytically, and we show that this ideal behavior is first-order insensitive to dominant experimental imperfections. We expect this mixer to allow significant advances in high- <a:math xmlns:a=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"> <a:mi>Q</a:mi> </a:math> control, readout, and amplification.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147893177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Fast Multiplexed Superconducting-Qubit Readout with Intrinsic Purcell Filtering Using a Multiconductor Transmission Line 利用多导体传输线进行内禀Purcell滤波的快速多路超导量子比特读出

PRX quantum : a Physical Review journal Pub Date : 2025-06-05 DOI: 10.1103/prxquantum.6.020345

Peter Spring, Luka Milanovic, Yoshiki Sunada, Shiyu Wang, Arjan F. van Loo, Shuhei Tamate, Yasunobu Nakamura

{"title":"Fast Multiplexed Superconducting-Qubit Readout with Intrinsic Purcell Filtering Using a Multiconductor Transmission Line","authors":"Peter Spring, Luka Milanovic, Yoshiki Sunada, Shiyu Wang, Arjan F. van Loo, Shuhei Tamate, Yasunobu Nakamura","doi":"10.1103/prxquantum.6.020345","DOIUrl":"https://doi.org/10.1103/prxquantum.6.020345","url":null,"abstract":"Fast and accurate qubit measurement remains a critical challenge on the path to fault-tolerant quantum computing. In superconducting quantum circuits, fast qubit measurement has been achieved using a dispersively coupled resonator with a large externally limited linewidth. This necessitates the use of a Purcell filter that protects the qubit from relaxation through the readout channel. Here, we show that a readout resonator and filter resonator, coupled to each other both capacitively and inductively via a multiconductor transmission line, can produce a compact notch-filter circuit that effectively eliminates the Purcell decay channel through destructive interference. By utilizing linewidths as large as 42 MHz, we perform simultaneous readout of four qubits using a 56-ns integration window and benchmark an average assignment fidelity of 99.77%, with the highest qubit assignment fidelity exceeding 99.9%. Including the simulated readout ring-down time, the total readout duration was between 115 and 215 ns for the four qubits, which we anticipate can be reduced to around 100 ns with active ring-down pulse shaping. These results demonstrate a significant advancement in speed and fidelity for multiplexed superconducting-qubit readout.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"http://link.aps.org/pdf/10.1103/PRXQuantum.6.020345","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147908006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

24 Days-Stable CNOT Gate on Fluxonium Qubits with Over 99.9% Fidelity Fluxonium量子比特上24天稳定CNOT门，保真度超过99.9%

PRX quantum : a Physical Review journal Pub Date : 2025-03-11 DOI: 10.1103/prxquantum.6.010349

Wei-Ju Lin, Hyunheung Cho, Yinqi Chen, Maxim Vavilov, Chen Wang, Vladimir Manucharyan

{"title":"24 Days-Stable CNOT Gate on Fluxonium Qubits with Over 99.9% Fidelity","authors":"Wei-Ju Lin, Hyunheung Cho, Yinqi Chen, Maxim Vavilov, Chen Wang, Vladimir Manucharyan","doi":"10.1103/prxquantum.6.010349","DOIUrl":"https://doi.org/10.1103/prxquantum.6.010349","url":null,"abstract":"Fluxonium qubit is a promising elementary building block for quantum information processing due to its long coherence time combined with a strong anharmonicity. In this paper, we realize a 60-ns direct gate on two inductively coupled fluxoniums, which behave almost exactly as a pair of transversely coupled spin-<a:math xmlns:a=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\" overflow=\"scroll\"><a:mn>1</a:mn><a:mo>/</a:mo><a:mn>2</a:mn></a:math> systems. The -gate fidelity, estimated using randomized benchmarking, was as high as 99.94%. Furthermore, the fidelity remains above 99.9% for 24 days without any recalibration between measurements. Compared with the 99.96% fidelity of a 60-ns identity gate, our data brings the investigation of the nondecoherence-related errors during logical operations down to <d:math xmlns:d=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\" overflow=\"scroll\"><d:mn>2</d:mn><d:mo>×</d:mo><d:msup><d:mn>10</d:mn><d:mrow><d:mo>−</d:mo><d:mn>4</d:mn></d:mrow></d:msup></d:math>. The present result adds a simple and robust two-qubit gate into the still relatively small family of the “beyond three nines” gates on superconducting qubits.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147904119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 14

Preparing Schrödinger Cat States in a Microwave Cavity Using a Neural Network 利用神经网络在微波腔中制备Schrödinger Cat态

PRX quantum : a Physical Review journal Pub Date : 2025-01-31 DOI: 10.1103/prxquantum.6.010321

Hector Hutin, Pavlo Bilous, Chengzhi Ye, Sepideh Abdollahi, Loris Cros, Tom Dvir, Tirth Shah, Yonatan Cohen, Audrey Bienfait, Florian Marquardt, Benjamin Huard

{"title":"Preparing Schrödinger Cat States in a Microwave Cavity Using a Neural Network","authors":"Hector Hutin, Pavlo Bilous, Chengzhi Ye, Sepideh Abdollahi, Loris Cros, Tom Dvir, Tirth Shah, Yonatan Cohen, Audrey Bienfait, Florian Marquardt, Benjamin Huard","doi":"10.1103/prxquantum.6.010321","DOIUrl":"https://doi.org/10.1103/prxquantum.6.010321","url":null,"abstract":"Scaling up quantum computing devices requires solving ever more complex quantum control tasks. Machine learning has been proposed as a promising approach to tackle the resulting challenges. However, experimental implementations are still scarce. In this work, we demonstrate experimentally a neural-network-based preparation of Schrödinger cat states in a cavity coupled dispersively to a qubit. We show that it is possible to teach a neural network to output optimized control pulses for a whole family of quantum states. After being trained in simulations, the network takes a description of the target quantum state as input and rapidly produces the pulse shape for the experiment, without any need for time-consuming additional optimization or retraining for different states. Our experimental results demonstrate more generally how deep neural networks and transfer learning can produce efficient simultaneous solutions to a range of quantum control tasks, which will benefit not only state preparation but also parametrized quantum gates.","PeriodicalId":74587,"journal":{"name":"PRX quantum : a Physical Review journal","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147889369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Blueprint for All-to-All-Connected Superconducting Spin Qubits 全对全连接超导自旋量子比特的蓝图

PRX quantum : a Physical Review journal Pub Date : 2025-01-13 DOI: 10.1103/prxquantum.6.010308

Marta Pita‐Vidal, Jaap J. Wesdorp, Christian Kraglund Andersen

引用次数: 13