Real-time vector field tracking with a cold-atom magnetometer

TL;DR

This paper presents a rapid, high-sensitivity three-axis cold-atom magnetometer using optically-trapped rubidium gas, capable of real-time vector magnetic field measurements with sub-nanotesla sensitivity and high spatial resolution.

Contribution

The work introduces a novel cold-atom magnetometer that performs real-time, three-axis magnetic field measurements with shot-noise limited sensitivity and detailed sensitivity analysis.

Findings

Achieves sub-nT sensitivity in 1 ms measurement

Provides three-axis magnetic field and gradient measurements

Demonstrates high spatial resolution of approximately 20 μm

Abstract

We demonstrate a fast three-axis optical magnetometer using cold, optically-trapped $^{87}$Rb gas as a sensor. By near-resonant Faraday rotation we record the free-induction decay following optical pumping along two orthogonal axes to obtain the three field components and one gradient component. A single measurement achieves shot-noise limited sub-nT sensitivity in 1 ms, with transverse spatial resolution of $\sim$ 20 $\mu$m. We make a detailed analysis of the shot-noise-limited sensitivity.