# Quantum enhanced optomechanical magnetometry

## TL;DR

This paper demonstrates that quantum correlated light, specifically phase squeezed light, can enhance the sensitivity and bandwidth of chip-scale optomechanical magnetometers, achieving significant improvements over classical approaches.

## Contribution

The work introduces a silicon-chip based cavity optomechanical magnetometer utilizing phase squeezed light to suppress shot noise and expand bandwidth, a novel integration of quantum optics with sensor technology.

## Key findings

- 20% improvement in magnetic field sensitivity
- Bandwidth increased by 50% due to quantum squeezing
- First demonstration of quantum enhancement in chip-scale magnetometry

## Abstract

The resonant enhancement of both mechanical and optical response in microcavity optomechanical devices allows exquisitely sensitive measurements of stimuli such as acceleration, mass and magnetic fields. In this work, we show that quantum correlated light can improve the performance of such sensors, increasing both their sensitivity and their bandwidth. Specifically, we develop a silicon-chip based cavity optomechanical magnetometer that incorporates phase squeezed light to suppress optical shot noise. At frequencies where shot noise is the dominant noise source this allows a 20% improvement in magnetic field sensitivity. Furthermore, squeezed light broadens the range of frequencies at which thermal noise dominates, which has the effect of increasing the overall sensor bandwidth by 50%. These proof-of-principle results open the door to apply quantum correlated light more broadly in chip-scale sensors and devices.