Enhanced sensing of anharmonicities in a gain-based anti-PT symmetric system  

作　　者：Ya-Wei Zeng Tian-Le Yang Qi-Yin Lin Wan-Jun Su 曾亚伟;杨天乐;林琪茵;苏万钧(Fujian Key Laboratory of Quantum Information and Quantum Optics and Department of Physics,Fuzhou University,Fuzhou 350116,China)

机构地区：[1]Fujian Key Laboratory of Quantum Information and Quantum Optics and Department of Physics,Fuzhou University,Fuzhou 350116,China

出　　处：《Chinese Physics B》2024年第12期86-94,共9页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11704058 and 12174058)。

摘　　要：We study the enhanced sensing of weak anharmonicities in a gain-based cavity-magnon-waveguide coupled system.By dissipatively coupling the two subsystems through a mediating waveguide,the Hamiltonian of the system is tailored to be anti-parity-time symmetric.Unique to the gain condition,the eigenvalues exhibit two singularities with linewidth suppression,distinguishing them from those of gain-free systems.Under the gain condition,a counter-intuitive bistable signature emerges even at low drive powers.As the effective gain approaches a certain value,this bistability yields a significantly enhanced spin-current response of the magnon mode.Consequently,the sensitivity,quantified by an enhancement factor,is enhanced remarkably compared to the linewidth suppression scenario.Moreover,the high enhancement factor can be sustained over a broad gain-bandwidth and also stays large even when the coherent coupling becomes considerably strong.Based on the integrated cavity-magnon-waveguide systems,this scheme can be used for sensing different physical quantities related to the Kerr-type nonlinearity and has potential applications in high-precision measuring microwave-signal nonlinearities.

关 键 词：SENSING nonlinearities anti-parity-time symmetry BISTABILITY 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] O413[自动化与计算机技术—控制科学与工程]