Vacuum squeezing enhanced micrometer scale vapor cell magnetometer

TL;DR

This paper demonstrates an optical magnetometer using vacuum-squeezed light in a micrometer-scale rubidium vapor cell, achieving enhanced sensitivity and showcasing potential for compact atomic sensors.

Contribution

It introduces the use of vacuum-squeezed light in a micrometer-scale vapor cell magnetometer, improving sensitivity and compactness over previous designs.

Findings

Achieved -3 dB vacuum squeezing in the noise spectral window of 100 Hz to several MHz.

Demonstrated magnetic field sensitivity of approximately 1 pT/√Hz.

Showcased potential for low-power, compact atomic sensors with enhanced performance.

Abstract

We report on an optical magnetometer enhanced by vacuum-squeezed light, employing an Mx magnetometer based on $^{87}$Rb vapor in a micrometer-scale cell (~100 $\mu$m). Using the well-established polarization self-rotation effect in a room-temperature $^{87}$Rb vapor cell, we achieve -3 dB of vacuum squeezing within the noise spectral window of 100 Hz to several MHz, corresponding to 3.5 dB squeezing when accounting for optical losses. Leveraging this level of squeezing, we demonstrate a magnetic field sensitivity of approx. 1 pT$/$$\sqrt{Hz}$. The combination of vacuum-squeezed light and micrometer-scale vapor cells paves the way for compact, low-power-consumption atomic sensors with enhanced performance.