npj Quantum Information最新文献_第3页

Improved strategies for fermionic quantum simulation with global interactions 具有全局相互作用的费米子量子模拟改进策略

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-27 DOI: 10.1038/s41534-026-01223-0

Thierry N. Kaldenbach, Erik Schultheis, Niklas Stewen, Gabriel Breuil

引用次数: 0

When quantum and classical models disagree: learning beyond minimum norm least square 当量子模型和经典模型不一致时：学习超越最小范数最小二乘

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-27 DOI: 10.1038/s41534-026-01217-y

Slimane Thabet, Léo Monbroussou, Eliott Z. Mamon, Jonas Landman

{"title":"When quantum and classical models disagree: learning beyond minimum norm least square","authors":"Slimane Thabet, Léo Monbroussou, Eliott Z. Mamon, Jonas Landman","doi":"10.1038/s41534-026-01217-y","DOIUrl":"https://doi.org/10.1038/s41534-026-01217-y","url":null,"abstract":"Quantum Machine Learning algorithms based on Variational Quantum Circuits (VQCs) are important candidates for useful application of quantum computing. It is known that a VQC is a linear model in a feature space determined by its architecture. Such models can be compared to classical ones using various sets of tools, and surrogate models designed to classically approximate their results were proposed. At the same time, quantum advantages for learning tasks have been proven in the case of discrete data distributions and cryptography primitives. In this work, we propose a framework to avoid Random Feature approximation techniques. Using previous results, we establish conditions on the weight vectors of the quantum models that are necessary to avoid these dequantization methods. We show that this theory is compatible with previously proven quantum advantages on discrete inputs, and provides examples of advantages for continuous inputs. This separation is connected to large weight vector norm, and we suggest that this can only happen with a high dimensional feature map. Our results demonstrate that it is possible to design quantum models that cannot be classically approximated with good generalization. In addition, we provide a method to verify that the necessary condition is respected for a quantum model. Finally, we discuss how concentration issues must be considered to design such instances. We expect that our work will be a starting point to design near-term quantum models that avoid dequantization methods by ensuring non-classical convergence properties, and to identify existing quantum models that can be classically approximated.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"1 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147536116","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

Robust photon blockade with hybrid molecular optomechanics 基于混合分子光力学的鲁棒光子阻滞

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-23 DOI: 10.1038/s41534-026-01220-3

Jian Tang, Baijun Li, Bin Yin, Tian-Xiang Lu, Ran Huang, Franco Nori, Hui Jing

{"title":"Robust photon blockade with hybrid molecular optomechanics","authors":"Jian Tang, Baijun Li, Bin Yin, Tian-Xiang Lu, Ran Huang, Franco Nori, Hui Jing","doi":"10.1038/s41534-026-01220-3","DOIUrl":"https://doi.org/10.1038/s41534-026-01220-3","url":null,"abstract":"Molecular cavity optomechanical systems, featuring ultrahigh vibrational frequencies and strong light-matter interactions, hold significant promise for advancing applications in quantum science and technology. Specifically, by introducing metallic nanoparticles into microcavities, hybrid molecular cavity optomechanical systems can further enhance optical quality factors and system tunabilities, which enable scalable and controllable quantum platforms. In this study, we propose how to realize robust photon blockade, i.e., strong photon antibunching with arbitrary detuning conditions, by combining degenerate optical parametric amplification with a hybrid molecular cavity optomechanical system. More interesting, we find near-perfect optomechanical photon blockade at room temperature, which is robust against temperature and optical dissipation. In addition, our approach can release the strict condition of high temporal resolution by combining features of conventional and unconventional photon blockade. Our approach offers a feasible route to study intriguing quantum effects in hybrid molecular cavity optomechanical systems, and holds promise for applications in nonclassical state engineering, quantum sensing, and photonic precision measurements.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"18 3 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147496796","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

Discovery of ST2 centers in natural and CVD diamond 在天然金刚石和CVD金刚石中发现ST2中心

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-16 DOI: 10.1038/s41534-025-01116-8

Jonas Foglszinger, Andrej Denisenko, Georgy V. Astakhov, Lev Kazak, Petr Siyushev, Alexander M. Zaitsev, Jens Fuhrmann, Matthias Schreck, Fedor Jelezko, Roman Kolesov, Jörg Wrachtrup

{"title":"Discovery of ST2 centers in natural and CVD diamond","authors":"Jonas Foglszinger, Andrej Denisenko, Georgy V. Astakhov, Lev Kazak, Petr Siyushev, Alexander M. Zaitsev, Jens Fuhrmann, Matthias Schreck, Fedor Jelezko, Roman Kolesov, Jörg Wrachtrup","doi":"10.1038/s41534-025-01116-8","DOIUrl":"https://doi.org/10.1038/s41534-025-01116-8","url":null,"abstract":"The ST2 center is an optically addressable point defect in diamond that facilitates spin initialization and readout at room temperature. However, while this study presents the discovery of photostable ST2 centers first observed in a natural diamond and provides a reliable technique for artificially creating them, its chemical structure remains unknown. To assess the potential of ST2, we map out its basic optical characteristics, reveal its electronic level structure, and quantify the intrinsic transition rates. Furthermore, we investigate its response to microwaves, static magnetic fields, and the polarization of excitation laser light, revealing twelve inequivalent orientations of the ST2 center. Simultaneous exposure to microwaves and static magnetic fields also reveals an exceptionally wide acceptance angle for sensing strong magnetic fields, unlike the well-established NV center, which is sensitive only within a narrow cone aligned with its symmetry axis. This finding establishes the ST2 center as a highly promising candidate for nanoscale quantum sensing.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"52 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147465515","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

Negativity percolation in continuous-variable quantum networks 连续变量量子网络中的负性渗透

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-14 DOI: 10.1038/s41534-026-01210-5

Yaqi Zhao, Kan He, Yongtao Zhang, Jinchuan Hou, Jianxi Gao, Shlomo Havlin, Xiangyi Meng

{"title":"Negativity percolation in continuous-variable quantum networks","authors":"Yaqi Zhao, Kan He, Yongtao Zhang, Jinchuan Hou, Jianxi Gao, Shlomo Havlin, Xiangyi Meng","doi":"10.1038/s41534-026-01210-5","DOIUrl":"https://doi.org/10.1038/s41534-026-01210-5","url":null,"abstract":"Quantum networks (QNs) have been predominantly driven by discrete-variable (DV) architectures. Yet, optical platforms naturally generate Gaussian states—the common states of continuous-variable (CV) systems, making CV-based QNs an attractive route toward scalable, chip-integrated quantum computation and communication. To bridge the gap between well-studied DV entanglement percolation theories and their CV counterpart, we introduce a Gaussian-to-Gaussian entanglement distribution scheme that deterministically transports two-mode squeezed vacuum states across large CV networks. Analysis of the scheme’s collective behavior using statistical-physics methods reveals a new form of entanglement percolation—negativity percolation theory (NegPT)—characterized by a bounded entanglement measure called the ratio negativity. We discover that NegPT exhibits a mixed-order phase transition, marked simultaneously by both an abrupt change in global entanglement and a long-range correlation between nodes. This distinctive behavior places CV-based QNs in a new universality class, fundamentally distinct from DV systems. Additionally, the abruptness of this transition introduces a critical vulnerability of CV-based QNs: conventional feedback mechanism becomes inherently unstable near the threshold, highlighting practical implications for stabilizing large-scale CV-based QNs. Our results unify statistical models for CV-based entanglement distribution and uncover previously unexplored critical phenomena unique to CV systems, providing valuable insights and guidelines essential for developing robust, feedback-stabilized QNs.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"86 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147454741","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

Experimental secure multiparty computation from quantum oblivious transfer with bit commitment 基于位承诺的量子无关传输的实验安全多方计算

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-14 DOI: 10.1038/s41534-026-01219-w

Kai-Yi Zhang, An-Jing Huang, Kun Tu, Ming-Han Li, Chi Zhang, Wei Qi, Ya-Dong Wu, Yu Yu

引用次数: 0

Digitized counterdiabatic quantum critical dynamics 数字化反绝热量子临界动力学

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-13 DOI: 10.1038/s41534-026-01208-z

Anne-Maria Visuri, Alejandro Gomez Cadavid, Balaganchi A. Bhargava, Sebastián V. Romero, András Grabarits, Pranav Chandarana, Enrique Solano, Adolfo del Campo, Narendra N. Hegade

{"title":"Digitized counterdiabatic quantum critical dynamics","authors":"Anne-Maria Visuri, Alejandro Gomez Cadavid, Balaganchi A. Bhargava, Sebastián V. Romero, András Grabarits, Pranav Chandarana, Enrique Solano, Adolfo del Campo, Narendra N. Hegade","doi":"10.1038/s41534-026-01208-z","DOIUrl":"https://doi.org/10.1038/s41534-026-01208-z","url":null,"abstract":"We experimentally demonstrate that a digitized counterdiabatic quantum protocol reduces the number of topological defects created during a fast quench across a quantum phase transition. To show this, we perform quantum simulations of one- and two-dimensional transverse-field Ising models driven from the paramagnetic to the ferromagnetic phase. We utilize superconducting cloud-based quantum processors with up to 156 qubits. Our data reveal that the digitized counterdiabatic protocol reduces defect formation by up to 48% in the fast-quench regime–an improvement hard to achieve through digitized quantum annealing under current noise levels. The experimental results closely match theoretical and numerical predictions at short evolution times before deviating at longer times due to hardware noise. In one dimension, we derive an analytic solution for the defect number distribution in the fast-quench limit. For two-dimensional geometries, where analytical solutions are unknown and numerical simulations are challenging, we use advanced matrix product state methods. Our findings indicate a practical way to control topological defect formation during fast quenches and highlight the utility of counterdiabatic protocols for quantum optimization and quantum simulation in material design on current quantum processors.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"33 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147454746","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

Degenerate quantum erasure decoding 简并量子擦除解码

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-13 DOI: 10.1038/s41534-026-01212-3

Kao-Yueh Kuo, Yingkai Ouyang

引用次数: 0

Superiority of Krylov shadow tomography in estimating quantum Fisher information: from bounds to exactness Krylov阴影层析成像在估计量子Fisher信息中的优势：从界到精度

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-12 DOI: 10.1038/s41534-026-01216-z

Yuan-Hao Wang, Da-Jian Zhang

引用次数: 0

QKAN: quantum Kolmogorov-Arnold networks with applications in machine learning and multivariate state preparation QKAN：量子Kolmogorov-Arnold网络在机器学习和多元状态准备中的应用

IF 7.6 1区物理与天体物理

npj Quantum Information Pub Date : 2026-03-11 DOI: 10.1038/s41534-026-01202-5

Petr Ivashkov, Po-Wei Huang, Kelvin Koor, Lirandë Pira, Patrick Rebentrost

{"title":"QKAN: quantum Kolmogorov-Arnold networks with applications in machine learning and multivariate state preparation","authors":"Petr Ivashkov, Po-Wei Huang, Kelvin Koor, Lirandë Pira, Patrick Rebentrost","doi":"10.1038/s41534-026-01202-5","DOIUrl":"https://doi.org/10.1038/s41534-026-01202-5","url":null,"abstract":"We introduce quantum Kolmogorov-Arnold networks (QKAN), a quantum algorithmic framework inspired by the recently proposed Kolmogorov-Arnold Networks (KAN). QKAN inherits the compositional structure of KAN and is based on block-encodings, constructed recursively from a single layer using quantum singular value transformation. We demonstrate the algorithmic utility of QKAN in two applications. First, we introduce and analyze QKAN as a quantum learning model, treating the eigenvalues of block-encoded matrices as neurons and applying parametrized activation functions on the edges of the network. We show that QKAN is a wide-and-shallow neural architecture, where shallow depth is compensated by exponentially wide layers whenever efficient block-encodings of inputs are available. We further discuss how to parametrize and train QKAN using parametrized quantum circuits and quantum linear algebra subroutines. Second, we demonstrate that QKAN can serve as a multivariate quantum state-preparation protocol for functions with shallow compositional structure. We demonstrate this by efficiently preparing a multivariate Gaussian quantum state using a two-layer QKAN. Looking forward, we anticipate that QKAN’s compositional and modular design will enable new applications in quantum machine learning and quantum state preparation.","PeriodicalId":19212,"journal":{"name":"npj Quantum Information","volume":"108 1","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147394038","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