npj Quantum Information最新文献_第6页

An efficient quantum algorithm for ab initio approximations of non-linear response functions 非线性响应函数从头逼近的有效量子算法

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-09 DOI: 10.1038/s41534-025-01026-9

Tyler Kharazi, Torin F. Stetina, Liwen Ko, Guang Hao Low, K. Birgitta Whaley

{"title":"An efficient quantum algorithm for ab initio approximations of non-linear response functions","authors":"Tyler Kharazi, Torin F. Stetina, Liwen Ko, Guang Hao Low, K. Birgitta Whaley","doi":"10.1038/s41534-025-01026-9","DOIUrl":"https://doi.org/10.1038/s41534-025-01026-9","url":null,"abstract":"We develop and analyze a fault-tolerant quantum algorithm for non-linear response properties of molecular and condensed phase systems. We consider a semi-classical description in which the electronic degrees of freedom are treated quantum mechanically and the light is treated as a classical field interacting via the electric dipole approximation. We use the technique of eigenstate filtering, to efficiently resolve excitation energies for dominant dipole transitions. When applied to the electronic structure Hamiltonian with double factorized representation, each significant spectral line can be approximated to a width of ±γ, and to a height of ±ϵ with (Oleft({N}^{6}{eta }^{2}{gamma }^{-1}{epsilon }^{-1}log (1/epsilon )right)) queries to the block encoding of the unperturbed electronic structure Hamiltonian for η electrons over N basis functions. These quantities can be used to compute the nth order response functions for non-linear spectroscopies under limited assumptions using (widetilde{O}left({N}^{5n+1}{eta }^{n+1}/{gamma }^{n}epsilon right)) queries to the block encoding of the Hamiltonian.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"89 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144252766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

A measurement-device-independent quantum key distribution network using optical frequency comb 基于光频梳的独立于测量设备的量子密钥分配网络

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-09 DOI: 10.1038/s41534-025-01052-7

Wenhan Yan, Xiaodong Zheng, Wenjun Wen, Liangliang Lu, Yifeng Du, Yan-Qing Lu, Shining Zhu, Xiao-Song Ma

引用次数: 0

Lindblad-like quantum tomography for non-Markovian quantum dynamical maps 非马尔可夫量子动态映射的Lindblad-like量子层析成像

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-07 DOI: 10.1038/s41534-025-01044-7

S. Varona, M. Müller, A. Bermudez

{"title":"Lindblad-like quantum tomography for non-Markovian quantum dynamical maps","authors":"S. Varona, M. Müller, A. Bermudez","doi":"10.1038/s41534-025-01044-7","DOIUrl":"https://doi.org/10.1038/s41534-025-01044-7","url":null,"abstract":"We introduce Lindblad-like quantum tomography (LℓQT) as a quantum characterization technique of time-correlated noise in quantum information processors. This approach enables the estimation of time-local master equations, including their possible negative decay rates, by maximizing a likelihood function subject to dynamical constraints. We discuss LℓQT for the dephasing dynamics of single qubits in detail, which allows for a neat understanding of the importance of including multiple snapshots of the quantum evolution in the likelihood function, and how these need to be distributed in time depending on the noise characteristics. By a detailed comparative study employing both frequentist and Bayesian approaches, we assess the accuracy and precision of LℓQT of a dephasing quantum dynamical map that goes beyond the Lindblad limit, focusing on two different microscopic noise models that can be realised in either trapped-ion or superconducting-circuit architectures. We explore the optimization of the distribution of measurement times to minimize the estimation errors, assessing the superiority of each learning scheme conditioned on the degree of non-Markovinity of the noise, and setting the stage for future experimental designs of non-Markovian quantum tomography.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"464 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144236873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Error crafting in mixed quantum gate synthesis 混合量子门合成中的错误加工

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-06 DOI: 10.1038/s41534-025-01032-x

Nobuyuki Yoshioka, Seiseki Akibue, Hayata Morisaki, Kento Tsubouchi, Yasunari Suzuki

引用次数: 0

An invitation to the sample complexity of quantum hypothesis testing 量子假设检验的样本复杂性

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-05 DOI: 10.1038/s41534-025-00980-8

Hao-Chung Cheng, Nilanjana Datta, Nana Liu, Theshani Nuradha, Robert Salzmann, Mark M. Wilde

引用次数: 0

Unveiling quantum phase transitions from traps in variational quantum algorithms 从变分量子算法的陷阱中揭示量子相变

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-04 DOI: 10.1038/s41534-025-01038-5

Chenfeng Cao, Filippo Maria Gambetta, Ashley Montanaro, Raul A. Santos

{"title":"Unveiling quantum phase transitions from traps in variational quantum algorithms","authors":"Chenfeng Cao, Filippo Maria Gambetta, Ashley Montanaro, Raul A. Santos","doi":"10.1038/s41534-025-01038-5","DOIUrl":"https://doi.org/10.1038/s41534-025-01038-5","url":null,"abstract":"Understanding quantum phase transitions in physical systems is fundamental to characterize their behavior at low temperatures. Achieving this requires both accessing good approximations to the ground state and identifying order parameters to distinguish different phases. Addressing these challenges, our work introduces a hybrid algorithm that combines quantum optimization with classical machine learning. This approach leverages the capability of near-term quantum computers to prepare locally trapped states through finite optimization. Specifically, we apply LASSO for identifying conventional phase transitions and the Transformer model for topological transitions, utilizing these with a sliding window scan of Hamiltonian parameters to learn appropriate order parameters and locate critical points. We validated the method with numerical simulations and real-hardware experiments on Rigetti’s Ankaa 9Q-1 quantum computer. This protocol provides a framework for investigating quantum phase transitions with shallow circuits, offering enhanced efficiency and, in some settings, higher precision-thus contributing to the broader effort to integrate near-term quantum computing and machine learning.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"36 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144218688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

A solid-state temporally multiplexed quantum memory array at the single-photon level 一种单光子水平的固态临时多路量子存储阵列

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-04 DOI: 10.1038/s41534-025-01042-9

Markus Teller, Susana Plascencia, Cristina Sastre Jachimska, Samuele Grandi, Hugues de Riedmatten

引用次数: 0

Ultra-high strained diamond spin register with coherent optical control 具有相干光学控制的超高应变金刚石自旋寄存器

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-03 DOI: 10.1038/s41534-025-01049-2

Marco Klotz, Andreas Tangemann, Alexander Kubanek

引用次数: 0

The genuinely multipartite nonlocality of graph states is model-dependent 图状态的真正多部非局部性是模型相关的

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-06-02 DOI: 10.1038/s41534-025-01024-x

Xavier Coiteux-Roy, Owidiusz Makuta, Fionnuala Curran, Remigiusz Augusiak, Marc-Olivier Renou

{"title":"The genuinely multipartite nonlocality of graph states is model-dependent","authors":"Xavier Coiteux-Roy, Owidiusz Makuta, Fionnuala Curran, Remigiusz Augusiak, Marc-Olivier Renou","doi":"10.1038/s41534-025-01024-x","DOIUrl":"https://doi.org/10.1038/s41534-025-01024-x","url":null,"abstract":"The notion of genuinely multipartite nonlocality (GMNL) was introduced to conceptualize the fact that nonclassical resources involving more than two parties in a nontrivial way may be needed to account for some quantum correlations. In this letter, we first recall the contradictions inherent to the historical definition of GMNL. Second, we turn to one of its redefinitions, called Local-Operations-and-Shared-Randomness GMNL (LOSR-GMNL), proving that all caterpillar graph states (including linear cluster states) have this second property. Finally, we conceptualize a third, alternative definition, which we call Local-Operations-and-Neighbour-Communication GMNL (LONC-GMNL), that is adapted to situations in which short-range communication between some parties might occur. We show that linear cluster states do not have this third property, while GHZ states do. Beyond its technical content, our letter illustrates that rigorous conceptual work is needed before applying the concepts of multipartite nonlocality or entanglement to benchmark the nonclassicality of some experimentally-produced quantum systems.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"13 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144193158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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

Cryogenic microwave link for quantum local area networks 量子局域网络低温微波链路

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2025-05-31 DOI: 10.1038/s41534-025-01046-5

W. K. Yam, M. Renger, S. Gandorfer, F. Fesquet, M. Handschuh, K. E. Honasoge, F. Kronowetter, Y. Nojiri, M. Partanen, M. Pfeiffer, H. van der Vliet, A. J. Matthews, J. Govenius, R. N. Jabdaraghi, M. Prunnila, A. Marx, F. Deppe, R. Gross, K. G. Fedorov

{"title":"Cryogenic microwave link for quantum local area networks","authors":"W. K. Yam, M. Renger, S. Gandorfer, F. Fesquet, M. Handschuh, K. E. Honasoge, F. Kronowetter, Y. Nojiri, M. Partanen, M. Pfeiffer, H. van der Vliet, A. J. Matthews, J. Govenius, R. N. Jabdaraghi, M. Prunnila, A. Marx, F. Deppe, R. Gross, K. G. Fedorov","doi":"10.1038/s41534-025-01046-5","DOIUrl":"https://doi.org/10.1038/s41534-025-01046-5","url":null,"abstract":"Scalable quantum information processing with superconducting circuits is expected to advance from individual processors located in single dilution refrigerators to more powerful distributed quantum computing systems. The realization of hardware platforms for quantum local area networks (QLANs) compatible with superconducting technology is of high importance in order to achieve a practical quantum advantage. Here, we present a fundamental prototype platform for a microwave QLAN based on a cryogenic link connecting two separate dilution cryostats over a distance of 6.6 m with a base temperature of 52 mK in the center. Superconducting microwave coaxial cables are employed to form a quantum communication channel between the distributed network nodes. We demonstrate the continuous-variable entanglement distribution between the remote dilution refrigerators in the form of two-mode squeezed microwave states, reaching squeezing of 2.10 ± 0.02 dB and negativity of 0.501 ± 0.011. Furthermore, we show that quantum entanglement is preserved at channel center temperatures up to 1 K, paving the way towards microwave quantum communication at elevated temperatures. Consequently, such a QLAN system can form the backbone for future distributed quantum computing with superconducting circuits.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"37 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144183757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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