High-order exceptional points in optomechanics

TL;DR

This paper investigates high-order exceptional points in optomechanical systems with coupled passive and active resonators, revealing their potential to significantly enhance mechanical damping and stiffness for low-power cooling.

Contribution

It demonstrates the emergence of genuine high-order exceptional points in optomechanical systems, extending the control of micromechanical devices beyond traditional two-state systems.

Findings

High-order exceptional points can be realized in coupled passive-active resonators.

Giant enhancement of mechanical damping and stiffness occurs near gain-loss balance.

Low-power mechanical cooling is facilitated by these high-order exceptional points.

Abstract

We study mechanical cooling in systems of coupled passive (lossy) and active (with gain) optical resonators. We find that for a driving laser which is red-detuned with respect to the cavity frequency, the supermode structure of the system is radically changed, featuring the emergence of genuine high-order exceptional points. This in turn leads to giant enhancement of both the mechanical damping and the spring stiffness, facilitating low-power mechanical cooling in the vicinity of gain-loss balance. This opens up new avenues of steering micromechanical devices with exceptional points beyond the lowest-order two.