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

TL;DR

This paper theoretically explores the emergence and behavior of various exceptional points in a magno-optomechanical system, revealing new dynamical phenomena and potential for engineering non-Hermitian phase transitions.

Contribution

It introduces a theoretical framework for observing and analyzing multiple types of exceptional points in a coupled magno-optomechanical system, including dissipative and parity-time symmetric EPs.

Findings

Observation of dissipative and PT-symmetric EPs in the system.

Identification of second and third-order pseudo-Hermitian EPs.

Distinct dynamical behaviors of mechanical modes around EPs.

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.