Nonreciprocal Phonon Laser

TL;DR

This paper introduces a nonreciprocal phonon laser system using a spinning resonator that achieves unidirectional phonon lasing, enabling potential applications in directional sound control and acoustic topological devices.

Contribution

It demonstrates the use of the optical Sagnac effect in a coupled optomechanical system to achieve unidirectional phonon lasing, a novel approach for nonreciprocal phononic devices.

Findings

Phonon lasing is unidirectional due to spinning resonator effects.

The system exhibits a modified mechanical gain and lower power threshold.

Potential applications include directional phonon switches and acoustic sensing.

Abstract

We propose nonreciprocal phonon lasing in a coupled cavity system composed of an optomechanical and a spinning resonator. We show that the optical Sagnac effect leads to significant modifications in both the mechanical gain and the power threshold for phonon lasing. More importantly, the phonon lasing in this system is unidirectional, that is the phonon lasing takes place when the coupled system is driven in one direction but not the other. Our work establishes the potential of spinning optomechanical devices for low-power mechanical isolation and unidirectional amplification. This provides a new route, well within the reach of current experimental abilities, to operate cavity optomechanics devices for such a wide range of applications as directional phonon switches, invisible sound sensing, and topological or chiral acoustics.