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arXiv · 2509.00724

Enhancement of quantum sensing in a dissipatively coupled two-mode system

Hao-Wen Zhang·Dong-Yang Wang·Cheng-Hua Bai·Tian-Xiang Lu·Shi-Lei Su
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Abstract

Quantum sensing near exceptional points (EPs) in non-Hermitian systems has shown promising sensitivity enhancements. However, practical applications are often hindered by structural complexity and strict parameter constraints. In this work, we introduce a simplified anti-parity-time (anti-PT) symmetric platform consisting of two independently cavities, which are indirectly coupled to each other by a shared dissipative environment. We demonstrate a significantly enhanced sensing response at the EPs compared to non-EP configurations. This improvement is attributed to the dominant second-order term in the Laurent series expansion of the eigenvalue response to external perturbations- a characteristic feature of higher-order singularities at EPs. This mechanism not only reinforces the foundation for sensitivity enhancement but also offers a structurally compact and robust strategy for quantum sensing. Our results underscore the potential of anti-PT symmetric systems in enabling high-precision sensing technologies and bridging non-Hermitian physics with scalable photonic device platforms.

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Hao-Wen Zhang, Dong-Yang Wang, Cheng-Hua Bai, Tian-Xiang Lu, Shi-Lei Su. 2025-08-31. Enhancement of quantum sensing in a dissipatively coupled two-mode system. https://doi.org/10.1103/hm2c-zcy4

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