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arXiv · 2406.01060

Mechanical dynamics around higher-order exceptional point in magno-optomechanics

Wen-Di He·Xiao-Hong Fan·Ming-Yue Liu·Guo-Qiang Zhang·Hai-Chao Li·Wei Xiong
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Abstract

We theoretically study diverse exceptional points (EPs) in an experimentally feasible magno-optomechanics consisting of an optomechanical subsystem coupled to a magnomechanical subsystem via physically direct contact. By adiabatically eliminating both the cavity and the Kittel mode, dissipative and parity-time symmetric exceptional points can be observed. When only the cavity mode is eliminated, a second (third) -order pseudo-Hermitian EP emerges for nondegenerate (degenerate) mechanical modes. The distinct dynamical behavior of two mechanical modes around these EPs are further studied. Our proposal provides a promising way to engineer diverse EPs and quantify non-Hermitian phase transition with exceptional dynamical behavior in magno-optomechanics.

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Wen-Di He, Xiao-Hong Fan, Ming-Yue Liu, Guo-Qiang Zhang, Hai-Chao Li, Wei Xiong. 2024-06-03. Mechanical dynamics around higher-order exceptional point in magno-optomechanics. https://arxiv.org/abs/2406.01060

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