Yu Min, Li Xiangbei, Chu Yaoming, Mera Bruno, Ünal F Nur, Yang Pengcheng, Liu Yu, Goldman Nathan, Cai Jianming
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.
International Joint Laboratory on Quantum Sensing and Quantum Metrology, Huazhong University of Science and Technology, Wuhan 430074, China.
Natl Sci Rev. 2024 Feb 26;11(10):nwae065. doi: 10.1093/nsr/nwae065. eCollection 2024 Oct.
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.
通过量子费舍尔信息的基本概念，量子计量学与量子几何紧密相连。受拓扑物质研究进展的启发，最近有人提出能带结构的贝里曲率和陈数可以决定计量特性的严格下限，从而在拓扑学和量子计量学之间建立了紧密联系。在这项工作中，我们通过进行最优量子多参数估计并实现尽可能高的测量精度，首次对这种拓扑界限进行了实验验证。通过模拟陈绝缘体的能带结构，我们通过实验确定了拓扑相变过程中的计量潜力，并证明了在拓扑非平凡区域有显著增强。我们的工作为受拓扑学推动的计量应用打开了大门，对量子多体系统可能具有潜在影响。
