Enhanced weak force sensing through atom-based coherent noise cancellation in a hybrid cavity optomechanical system

TL;DR

This paper proposes a hybrid optomechanical system utilizing coherent quantum noise cancellation and an optical parametric amplifier to significantly improve weak force sensing by eliminating back action noise and reducing shot noise, surpassing the standard quantum limit.

Contribution

It introduces a novel hybrid cavity optomechanical scheme combining CQNC and OPA for enhanced weak force detection, including practical tuning and damping rate matching strategies.

Findings

Back action noise can be eliminated at all frequencies.

Quantum shot-noise can be suppressed at lower frequencies.

Force sensing surpasses the standard quantum limit.

Abstract

We investigate weak force-sensing based on coherent quantum noise cancellation in a nonlinear hybrid optomechanical system. The optomechanical cavity contains a moveable mechanical mirror, a fixed semitransparent mirror, an ensemble of ultracold atoms, and an optical parametric amplifier (OPA). Using the coherent quantum noise cancellation (CQNC) process, one can eliminate the back action noise at all frequencies. Also by tuning the OPA parameters, one can suppress the quantum shot-noise at lower frequencies than the resonant frequency. In the CQNC scheme, the damping rate of the mechanical oscillator matches the damping rate of the atomic ensemble, which is experimentally achievable even for a low-frequency mechanical oscillator with a high-quality factor. Elimination of the back action noise and suppression of the shot noise significantly enhance force sensing and thus overcome the standard quantum limit of weak force sensing. This hybrid scheme can play an essential role in the realization of quantum optomechanical sensors and quantum control.