Radiation-Pressure-Mediated Control of an Optomechanical Cavity

TL;DR

This paper demonstrates a method to control a detuned optomechanical cavity using radiation pressure and feedback, achieving self-locking and stabilization through optomechanical interaction and external feedback mechanisms.

Contribution

It introduces a novel approach combining radiation-pressure-induced self-locking with external feedback to stabilize a detuned optomechanical cavity.

Findings

Achieved intrinsic self-locking of the cavity below the optical spring resonance.

Demonstrated stabilization using amplitude modulation and feedback around the resonance.

Showed reduced susceptibility of the mirror to external disturbances.

Abstract

We describe and demonstrate a method to control a detuned movable-mirror Fabry-Perot cavity using radiation pressure in the presence of a strong optical spring. At frequencies below the optical spring resonance, self-locking of the cavity is achieved intrinsically by the optomechanical (OM) interaction between the cavity field and the movable end mirror. The OM interaction results in a high rigidity and reduced susceptibility of the mirror to external forces. However, due to a finite delay time in the cavity, this enhanced rigidity is accompanied by an anti-damping force, which destabilizes the cavity. The cavity is stabilized by applying external feedback in a frequency band around the optical spring resonance. The error signal is sensed in the amplitude quadrature of the transmitted beam with a photodetector. An amplitude modulator in the input path to the cavity modulates the light intensity to provide the stabilizing radiation pressure force.