Optomechanics with two-phonon driving

TL;DR

This paper explores how two-phonon driving in an optomechanical cavity enables phase-sensitive optical amplification, squeezing, and low-noise force detection, revealing unique spectral properties like negative photon temperature.

Contribution

It demonstrates that mechanical parametric driving can induce optical amplification and squeezing, and enables ultra-low noise force sensing in optomechanical systems.

Findings

Cavity mode inherits parametric amplification from mechanical driving.

System achieves phase-sensitive amplification and squeezing of reflected light.

Spectral function can become negative, indicating negative photon temperature.

Abstract

We consider the physics of an optomechanical cavity subject to coherent two-phonon driving, i.e. degenerate parametric amplification of the mechanical mode. We show that in such a system, the cavity mode can effectively "inherit" parametric driving from the mechanics, yielding phase-sensitive amplification and squeezing of optical signals reflected from the cavity. We also demonstrate how such a system can be used to perform single-quadrature detection of a near-resonant narrow-band force applied to the mechanics with extremely low added noise from the optics. The system also exhibits strong differences from a conventional degenerate parametric amplifier: in particular, the cavity spectral function can become negative, indicating a negative effective photon temperature.