Quantum Science and Technology最新文献

Quantum metrology of spin sensing with free space electrons 自由空间电子自旋传感的量子计量

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-16 DOI: 10.1088/2058-9565/aeb56c

Santiago Beltràn-Romero,Michael Gaida,Philipp Haslinger,Dennis Raetzel,Stefan Nimmrichter

{"title":"Quantum metrology of spin sensing with free space electrons","authors":"Santiago Beltràn-Romero,Michael Gaida,Philipp Haslinger,Dennis Raetzel,Stefan Nimmrichter","doi":"10.1088/2058-9565/aeb56c","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb56c","url":null,"abstract":"Abstract Recent advances in transmission electron microscopy (TEM) have opened the path toward spin resonance spectroscopy with single-spin sensitivity. To assess this potential, we investigate the quantum precision limits for sensing magnetic moments with free-electron probes. Using a scattering model where an electron wavepacket interacts with a localized spin, we study two metrological tasks: estimating the magnitude of the magnetic moment and discriminating the presence of a spin. The sensitivity for a given measurement setting is generally determined by the classical Fisher information, which we benchmark against the quantum bound optimized over all measurements. We find that conventional TEM imaging can saturate the quantum bound when backaction of the probe electron onto the spin state is negligible. We also find that, when backaction is relevant, one could do better by realizing a measurement of the electron's orbital angular momentum state. These results establish the quantum limits of spin sensing in TEM and guide the development of future experiments probing individual electron spins or nanoscale ensembles of nuclear spins.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"68 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantum work statistics and coherence effects in quenched bosonic Josephson junctions 猝灭玻色子Josephson结的量子功统计和相干效应

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-16 DOI: 10.1088/2058-9565/aeb56b

Mattia Orlandini,Stefano Gherardini,Lorenzo Buffoni,Beatrice Donelli

{"title":"Quantum work statistics and coherence effects in quenched bosonic Josephson junctions","authors":"Mattia Orlandini,Stefano Gherardini,Lorenzo Buffoni,Beatrice Donelli","doi":"10.1088/2058-9565/aeb56b","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb56b","url":null,"abstract":"Abstract We investigate the non-equilibrium work statistics originating from a sudden quench in a bosonic Josephson junction. In particular, by employing the Holstein-Primakoff approximation, the work statistics are analytically characterized in the weak-interaction regime, where the dynamics map onto a time-dependent quantum harmonic oscillator. For a junction initialized in the ground state of the pre-quench Hamiltonian, we demonstrate that the work statistics are governed by a negative binomial distribution, as occurs in fully-connected models driven across a critical point. Furthermore, we also consider initial superposition states containing quantum coherences in the energy basis. To characterize the corresponding work distributions, we employ Kirkwood-Dirac quasiprobabilities (KDQ). Even in the simplest case, when the junction is initialized in a superposition of the ground and second excited states, the KDQ distribution of work exhibits negative or complex values, reflecting non-classical features. Moreover, the coherence content of the initial state can be optimized to enhance the extractable work extracted from the quench, beyond classical bounds. Finally, we propose an experimental interferometric protocol to directly measure the characteristic function of the work distribution in experimentally accessible settings.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"411 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accuracy-cost trade-offs for reference VQE calculations of H 2 on IBM quantum hardware 在IBM量子硬件上对h2进行参考VQE计算的精度-成本权衡

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-15 DOI: 10.1088/2058-9565/aeb4e8

Julen Larrucea,Marita Oliv,Jeanette Miriam Lorenz

{"title":"Accuracy-cost trade-offs for reference VQE calculations of H\u0000 2\u0000 on IBM quantum hardware","authors":"Julen Larrucea,Marita Oliv,Jeanette Miriam Lorenz","doi":"10.1088/2058-9565/aeb4e8","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb4e8","url":null,"abstract":"Abstract Variational quantum eigensolver (VQE) calculations are widely used as reference workflows for assessing near-term quantum hardware, but practical guidance on their accuracy, runtime, and billed usage remains limited. Here, we present a hardware-validated reference dataset for variational ground-state energy calculations of the hydrogen molecule H 2 on several IBM Quantum processors available in 2025–2026. Using a standardized Qiskit Nature workflow, we benchmark the impact of shot count, backend choice, fermion-to-qubit mapping, optimizer behavior, resilience level, and execution mode on the achievable energy accuracy relative to exact diagonalization. For the H 2 /STO–3G configurations examined, circuit simplification through tapered mappings provides the most consistent accuracy gains, resilience level 1 improves accuracy at a substantial billed-usage premium, and session-based execution yields no systematic accuracy advantage over single-job execution despite markedly higher billed time. The dataset and analysis provide a transparent baseline for assessing current IBM Quantum hardware for quantum-chemistry applications and for estimating the runtime effort and billed usage that non-specialist users can expect from standard workflows.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"33 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

AMARQ: Adaptive multi-application routing for quantum networks 量子网络的自适应多应用路由

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-14 DOI: 10.1088/2058-9565/aeb43d

Lamarana Jallow,Majid I Khan

{"title":"AMARQ: Adaptive multi-application routing for quantum networks","authors":"Lamarana Jallow,Majid I Khan","doi":"10.1088/2058-9565/aeb43d","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb43d","url":null,"abstract":"Abstract Future quantum networks will have to support different applications on shared infrastructure, like fidelity-critical Quantum Key Distribution (QKD) and latency-sensitive Distributed Quantum Computing (DQC). The existing approaches for entanglement routing either optimise for a single application, or rely on sequential resource allocation, which results in inefficient resource utilisation, unfairness and degraded performance when multiple applications compete for shared network resources. In this paper, we propose AMARQ, a multi-objective Deep Q-Network (DQN) based routing framework to jointly serve heterogeneous QKD and DQC traffic on shared quantum infrastructure. The agent makes adaptive and application-aware routing decisions to dynamically balance the rigid fidelity and latency requirements of QKD and the high-throughput and elastic rate requirements of DQC. The reward function combines a successful-routing throughput term with a per-edge fidelity penalty and an end-of-episode failure penalty; per-flow latency is enforced as a QoS constraint, and inter-application fairness is enforced by a dedicated admission-control loop that reserves a dynamic QKD qubit pool. We assess the performance of AMARQ on grid topologies with 25 to 625 nodes. AMARQ attains a request success ratio above 85%, which is up to 32 percentage points higher than ESDI and 39 percentage points higher than Cicconetti, while keeping the end-to-end fidelity above 0.80 and the inference latency below 90~ms for all configurations.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"15 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantum batteries in two-dimensional material-based Josephson junctions 二维材料约瑟夫森结中的量子电池

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-13 DOI: 10.1088/2058-9565/aeb3ab

Vincenzo Varrica,Giulia Gemme,Francesco Maria Dimitri Pellegrino,Elisabetta Paladino,Maura Sassetti,Dario Ferraro

引用次数: 0

Zeno-enhanced probabilistic error cancellation with quantum error detection codes 量子错误检测码的芝诺增强概率错误消除

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-13 DOI: 10.1088/2058-9565/aeb3ad

Yi Yuan,Yuanchen Zhao,Liu Dong

{"title":"Zeno-enhanced probabilistic error cancellation with quantum error detection codes","authors":"Yi Yuan,Yuanchen Zhao,Liu Dong","doi":"10.1088/2058-9565/aeb3ad","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb3ad","url":null,"abstract":"Abstract Probabilistic error cancellation (PEC) is unbiased but suffers exponential sampling overhead set by noise-weighted circuit volume, whereas quantum error-detecting codes (QEDCs) remove many physical faults by stabilizer post-selection but leave an undetectable logical residue. We exploit this complementarity by using post-selection to map physical noise to a weaker accepted logical channel, and then applying PEC only to the residual channel. The resulting feedback-free QED+PEC scheme interleaves Clifford logical blocks, stabilizer measurements, post-selection, and probabilistic cancellation on accepted trajectories, without real-time decoding or active recovery. A key complication is that post-selection correlates accepted fault branches through stabilizer-commutation constraints, so the sparse Pauli-Lindblad factorization underlying bare PEC no longer applies directly. We therefore construct the inverse channel perturbatively: for fixed order $K$, only accepted fault branches up to order $K$ are retained, reducing preprocessing from $2^m$ branches to $O(m^K)$ per block. The order-$K$ protocol cancels the normalized post-selected channel through degree $K$, leaving a per-block error $O(W^{K+1})$ that accumulates at most linearly. For logical GHZ-state preparation with the $[[n,n-2,2]]$ Iceberg code under circuit-level depolarizing noise and ideal stabilizer measurements, first-order QED+PEC reaches $n=200$ physical qubits and lowers sampling overhead by three to four orders of magnitude relative to standard PEC while maintaining $Fsimeq0.956$. Syndrome-noise tests show that readout-only flips mainly increase post-selection cost, whereas noisy GHZ-assisted global stabilizer extraction can remove the advantage. This identifies a discrete-Zeno trade-off: cheap detection reshapes the effective channel PEC must invert, rather than simply adding overhead.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"32 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Variational noise mitigation in quantum circuits: the case of Quantum Fourier Transform 量子电路中的变分噪声抑制：以量子傅立叶变换为例

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-13 DOI: 10.1088/2058-9565/aeb3af

Rafael Gómez-Lurbe,Alexander Bernal,Armando Perez,Bryan Zaldívar,J Alberto Casas

{"title":"Variational noise mitigation in quantum circuits: the case of Quantum Fourier Transform","authors":"Rafael Gómez-Lurbe,Alexander Bernal,Armando Perez,Bryan Zaldívar,J Alberto Casas","doi":"10.1088/2058-9565/aeb3af","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb3af","url":null,"abstract":"Abstract We study a variational quantum algorithm (VQA) approach for improving the implementation of the Quantum Fourier Transform (QFT) under realistic noise conditions. We employ a training strategy based on mutually unbiased bases (MUBs), which probes the action of the noisy variational circuit over a global set of input states and promotes generalization beyond the training ensemble. We numerically study two- and three-qubit QFT implementations under noise models combining incoherent errors with coherent crosstalk, using calibration parameters derived from a quantum device. For the 2-qubit QFT, the optimized variational circuit consistently outperforms the corresponding noisy QFT in scenarios containing coherent noise and exhibits highly reproducible optimization across independent parameter initializations. The variational advantage persists in the direct 3-qubit optimization, although with a stronger dependence on initialization. We further show that reduced MUB training sets can retain most of the performance of the complete set while substantially reducing the number of training states, whereas training only on computational-basis states leads to markedly poorer generalization and a stronger dependence on parameter initialization. Finally, exploiting the recursive structure of the QFT, we demonstrate that an optimized 2-qubit variational block can be embedded into a 3-qubit QFT and improve its noisy implementation without retraining the complete circuit. These results highlight the potential of combining global state-space training with device-specific noise-aware variational optimization to improve small noisy quantum circuits and to explore the transfer of variationally learned noise resilience to larger constructions.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"80 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Towards multi-QPU quantum systems: Circuit mapping for high execution fidelity and low communication overhead 面向多qpu量子系统：高执行保真度和低通信开销的电路映射

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-13 DOI: 10.1088/2058-9565/aeb3ac

Longshan Xu,Edwin Sha,Weixuan Liu,Qingfeng Zhuge

{"title":"Towards multi-QPU quantum systems: Circuit mapping for high execution fidelity and low communication overhead","authors":"Longshan Xu,Edwin Sha,Weixuan Liu,Qingfeng Zhuge","doi":"10.1088/2058-9565/aeb3ac","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb3ac","url":null,"abstract":"Abstract Multi-quantum processing unit (multi-QPU) architectures have emerged as a promising route for scaling up quantum computing. However, quantum circuit execution across QPUs introduces remote operations, which have lower fidelity than local operations and require additional communication resources. Circuit mapping, which determines where quantum information and operations are placed, critically affects the number of required remote operations and, consequently, the reliability and efficiency of distributed execution. Here, we introduce NAVI, a communication- and noise-aware circuit mapping framework for multi-QPU systems. NAVI addresses three mapping decisions in a staged compiler workflow: how to partition qubits according to evolving interaction patterns, which communication mode should be used for remote operations, and which physical QPUs should host the resulting qubit partitions under heterogeneous noise. Across a diverse set of benchmark circuits, NAVI reduces cumulative execution error by 40% to 55% and communication resource consumption by 60% to 72% on average compared with existing methods.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"27 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Towards studying superconductivity in the Fermi-Hubbard model on Rydberg atoms 里德伯原子费米-哈伯德模型中超导性的研究

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-13 DOI: 10.1088/2058-9565/aeb3a7

Kubra Yeter-Aydeniz,Nora Bauer

{"title":"Towards studying superconductivity in the Fermi-Hubbard model on Rydberg atoms","authors":"Kubra Yeter-Aydeniz,Nora Bauer","doi":"10.1088/2058-9565/aeb3a7","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb3a7","url":null,"abstract":"Abstract We present a method for calculating the ground state energy of the Fermi-Hubbard model leveraging Rydberg atom processors and sample-based quantum diagonalization (SQD). By exploiting the perturbative relationship between the Fermi-Hubbard and Heisenberg models, the procedure samples from the Heisenberg model as prepared on the Rydberg atom processor, and uses the samples to diagonalize the Fermi-Hubbard model for large U . We include anisotropy and next-nearest-neighbor interactions and discuss the relevant regime for quasi-superconductivity in the 1-dimensional Fermi-Hubbard model. Numerical and experimental results on the Aquila quantum processor are presented for ground state energy calculations as well as the chemical potential. We find that the Heisenberg model sampling in the studied regime is sufficient to converge near to the ground state for up to 56 qubits, and we see a clear advantage of Rydberg atom sampling as opposed to random sampling even with 10 times more samples for diagonalization. We also present a gate-based implementation of the gate-based SQD algorithm on IBM Quantum hardware for 56-qubit Hubbard model as a benchmark. Finally, we provide a gap analysis for studying emergent superconductivity using this method.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"35 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantum randomness beyond projective measurements 超越投影测量的量子随机性

IF 6.7 2区物理与天体物理

Quantum Science and Technology Pub Date : 2026-10-13 DOI: 10.1088/2058-9565/aeb3a9

Fionnuala Curran

{"title":"Quantum randomness beyond projective measurements","authors":"Fionnuala Curran","doi":"10.1088/2058-9565/aeb3a9","DOIUrl":"https://doi.org/10.1088/2058-9565/aeb3a9","url":null,"abstract":"Abstract The unpredictability of quantum physics gives rise to intrinsic randomness. In an adversarial scenario, any additional degrees of freedom must be attributed to an eavesdropper with correlations to the measurement set-up. The true randomness is then quantified by the probability that she correctly guesses the measurement outcomes, optimised over all possible strategies.&#xD;Extremal measurements are appealing here, since they do not allow information to leak to such an eavesdropper. Beyond projective measurements, however, a simple question remains open: how much intrinsic randomness can be generated by a given extremal measurement? In a step towards solving it, we characterise the randomness generated by any unbiased extremal rank-one measurement acting on any state, solving the problem explicitly in dimension two. Four-outcome qubit measurements of this type are tomographic, so these results hold for fully source-device-dependent randomness too. The tetrahedral symmetric informationally complete (SIC) measurement, we find, has the least intrinsic randomness within this class. We also present the skewed SIC family of measurements, and use them to partially solve an open problem: we prove that 2 log d bits of randomness, the maximal amount, can be generated device-dependently (or source-device-independently) in any dimension in which there exists a SIC measurement.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"10 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149208773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0