Optomechanical interactions in non-Hermitian photonic molecules

TL;DR

This paper investigates how non-Hermitian properties in photonic molecules influence optomechanical interactions, revealing that PT symmetry isn't always optimal and that gain saturation can control oscillations, offering insights for novel device design.

Contribution

It provides a detailed analysis of optomechanical interactions in non-Hermitian photonic molecules, highlighting the effects of gain saturation and challenging the assumption that PT symmetry maximizes optomechanical coupling.

Findings

PT symmetry is not always optimal for maximum interaction

Stable steady states may not occur under CW excitation

Gain saturation can regulate unbounded oscillations

Abstract

We study optomechanical interactions in non-Hermitian photonic molecules that support two photonic states and one acoustic mode. The nonlinear steady-state solutions and their linear stability landscapes are investigated as a function of the system's parameters and excitation power levels. We also examine the temporal evolution of the system and uncover different regimes of nonlinear dynamics. Our analysis reveals several important results: (1) Parity-time ($\mathcal{PT}$) symmetry is not necessarily the optimum choice for maximum optomechanical interaction. (2) Stable steady-state solutions are not always reached under continuous wave (CW) optical excitations. (3) Accounting for gain saturation effects can regulate the behavior of the otherwise unbounded oscillation amplitudes. Our study provides a deeper insight into the interplay between optical non-Hermiticity and optomechanical coupling and can thus pave the way for new device applications.