Experimental demonstration of topological bounds in quantum metrology  

作　　者：Min Yu Xiangbei Li Yaoming Chu Bruno Mera F.NurÜnal Pengcheng Yang Yu Liu Nathan Goldman Jianming Cai 

机构地区：[1]School of Physics,Hubei Key Laboratory of Gravitation and Quantum Physics,Institute for Quantum Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China [2]International Joint Laboratory on Quantum Sensing and Quantum Metrology,Huazhong University of Science and Technology,Wuhan 430074,China [3]Advanced Institute for Materials Research(WPI-AIMR),Tohoku University,Sendai 980-8577,Japan [4]TCM Group,Cavendish Laboratory,University of Cambridge,Cambridge CB30HE,UK [5]Institut für Theoretische Physik and IQST,Universität Ulm,Ulm D-89081 Germany [6]Center for Nonlinear Phenomena and Complex Systems,UniversitéLibre de Bruxelles,Brussels B-1050,Belgium [7]Laboratoire Kastler Brossel,Collège de France,Paris 75005,France [8]Shanghai Key Laboratory of Magnetic Resonance,East China Normal University,Shanghai 200062,China

出　　处：《National Science Review》2024年第10期248-256,共9页国家科学评论（英文版）

基　　金：supported by the National Natural Science Foundation of China(12161141011 and 11874024);the National Key R&D Program of China(2018YFA0306600);Shanghai Key Laboratory of Magnetic Resonance(East China Normal University),the FR S-FNR S(Belgium),the ERC(Starting Grant TopoCold),the Royal Society under a Newton International Fellowship,the Marie Skłodowska-Curie programme of the European Commission 893915,the EOS(CHEQS project);Y.-M.C.is supported by the Young Scientists Fund of the National Natural Science Foundation of China(12304572);the fellowship of China Postdoctoral Science Foundation(2022M721256);M.Y.is supported by the fellowship of China Postdoctoral Science Foundation(2023M741270);Y.L.is supported by the BMBF under the funding program‘quantum technologies-from basic research to market’in the project Spinning(13N16215).

摘　　要：Quantum metrology is deeply connected to quantum geometry,through the fundamental notion of quantum Fisher information.Inspired by advances in topological matter,it was recently suggested that the Berry curvature and Chern numbers of band structures can dictate strict lower bounds on metrological properties,hence establishing a strong connection between topology and quantum metrology.In this work,we provide a first experimental verification of such topological bounds,by performing optimal quantum multi-parameter estimation and achieving the best possible measurement precision.By emulating the band structure of a Chern insulator,we experimentally determine the metrological potential across a topological phase transition,and demonstrate strong enhancement in the topologically non-trivial regime.Our work opens the door to metrological applications empowered by topology,with potential implications for quantum many-body systems.

关 键 词：quantum metrology multi-parameter estimation topological bounds Berry curvature Chern number topological phase transition 

分 类 号：O413[理学—理论物理]