中国物理B ›› 2025, Vol. 34 ›› Issue (12): 128402-128402.doi: 10.1088/1674-1056/adec5e

• • 上一篇    

Observation of exceptional points and realization of high sensitivity sensing in electric circuits

Jiaxi Cai(蔡家希)1, Xinyi Wang(王鑫怡)2, Xiaomin Zhang(张晓敏)1, Taoran Yue(乐陶然)1, and Jijun Wang(王纪俊)1†   

  1. 1 School of Physics and Electronic Engineering, Jiangsu University, Zhenjiang 212013, China;
    2 School of Electrical and Information Engineering, Jiangsu University, Zhenjiang 212013, China
  • 收稿日期:2025-05-28 修回日期:2025-07-03 接受日期:2025-07-07 发布日期:2025-11-25
  • 通讯作者: Jijun Wang E-mail:wjj4461@ujs.edu.cn
  • 基金资助:
    We gratefully acknowledge the financial support of the Natural Science Foundation of Jiangsu Province (Grant No. BK20231320).

Observation of exceptional points and realization of high sensitivity sensing in electric circuits

Jiaxi Cai(蔡家希)1, Xinyi Wang(王鑫怡)2, Xiaomin Zhang(张晓敏)1, Taoran Yue(乐陶然)1, and Jijun Wang(王纪俊)1†   

  1. 1 School of Physics and Electronic Engineering, Jiangsu University, Zhenjiang 212013, China;
    2 School of Electrical and Information Engineering, Jiangsu University, Zhenjiang 212013, China
  • Received:2025-05-28 Revised:2025-07-03 Accepted:2025-07-07 Published:2025-11-25
  • Contact: Jijun Wang E-mail:wjj4461@ujs.edu.cn
  • About author:2025-128402-250946.pdf
  • Supported by:
    We gratefully acknowledge the financial support of the Natural Science Foundation of Jiangsu Province (Grant No. BK20231320).

摘要: We explore the parity-time (PT)-symmetry breaking transition in a dimer circuit composed of two RLC resonators that are weakly coupled via an inductor. The energy behavior of this dimer circuit is reflected in the splitting or degeneracy of the systems eigenfrequencies as the gain-loss strength varies. Its dynamical properties can be described by a non-Hermitian Hamiltonian. The eigenfrequency spectrum of the system is divided by two critical points into three distinct regions: the symmetric region, the oscillatory growth region, and the fully exponential growth region. Building upon previous work on implementing the exceptional point (EP) in circuit systems, our study focuses on further exploring the variation patterns of circuit eigenfrequencies near the EP under weak coupling conditions. In addition, we construct a corresponding Dirac point (DP) circuit system for comparison. By leveraging the unique physical properties near both the EP and the DP, we further propose potential practical applications. Using perturbation theory and system simulations, we demonstrate that the square-root eigenfrequency splitting near the EP significantly enhances the sensitivity to small external perturbations, compared to the linear splitting behavior near the DP. This study presents promising prospects for next-generation sensing technologies.

关键词: parity-time symmetry, exceptional point, Dirac point, high sensitivity sensor

Abstract: We explore the parity-time (PT)-symmetry breaking transition in a dimer circuit composed of two RLC resonators that are weakly coupled via an inductor. The energy behavior of this dimer circuit is reflected in the splitting or degeneracy of the systems eigenfrequencies as the gain-loss strength varies. Its dynamical properties can be described by a non-Hermitian Hamiltonian. The eigenfrequency spectrum of the system is divided by two critical points into three distinct regions: the symmetric region, the oscillatory growth region, and the fully exponential growth region. Building upon previous work on implementing the exceptional point (EP) in circuit systems, our study focuses on further exploring the variation patterns of circuit eigenfrequencies near the EP under weak coupling conditions. In addition, we construct a corresponding Dirac point (DP) circuit system for comparison. By leveraging the unique physical properties near both the EP and the DP, we further propose potential practical applications. Using perturbation theory and system simulations, we demonstrate that the square-root eigenfrequency splitting near the EP significantly enhances the sensitivity to small external perturbations, compared to the linear splitting behavior near the DP. This study presents promising prospects for next-generation sensing technologies.

Key words: parity-time symmetry, exceptional point, Dirac point, high sensitivity sensor

中图分类号:  (Electronic circuits)

  • 84.30.-r
03.65.Vf (Phases: geometric; dynamic or topological) 03.65.Ta (Foundations of quantum mechanics; measurement theory) 07.07.Df (Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing)