Overcoming the Standard Quantum Limit with Electro-Optomechanical Hybrid System for Enhanced Force Sensing

TL;DR

This paper demonstrates how a hybrid electro-optomechanical system with quantum noise cancellation can surpass the standard quantum limit in force sensing by reducing back-action and shot noise.

Contribution

It introduces a novel hybrid system design and conditions for complete back-action cancellation, enabling enhanced force sensitivity beyond the SQL.

Findings

Achieved force sensitivity beyond the SQL with increased OPA gain.

Demonstrated suppression of back-action and shot noise in the system.

Reduced laser power needed for surpassing the SQL.

Abstract

We investigate the reduction of measurement-added noise in force sensing by analyzing its power spectral density (PSD) within a hybrid optomechanical system. The setup comprises of an optomechanical cavity equipped with a movable mirror which acts as the mechanical oscillator, a stationary semi-transparent mirror, a superconducting qubit, and an optical parametric amplifier (OPA). By utilizing the concept of coherent quantum noise cancellation (CQNC), we derive the conditions necessary for complete cancellation of back-action force, thereby enhancing force sensitivity. Furthermore, with the gradual increase in the OPA pump gains, we suppress the sensitivity beyond the standard quantum limit (SQL) at a lower value of laser power. The removal of back-action noise, along with the reduction of shot noise, improves force detection capabilities, thereby surpassing the standard quantum limit associated with weak force detection.