High-Resolution Magnetometry with a Spinor Bose-Einstein Condensate

TL;DR

This paper presents a high-resolution, highly sensitive magnetometer using a spinor Bose-Einstein condensate, achieving sensitivity comparable to SQUIDs and nearing the atom shot-noise limit, with potential for advanced quantum sensing.

Contribution

The authors demonstrate a novel magnetometry technique utilizing a spinor Bose-Einstein condensate for spatially resolved magnetic field measurements with unprecedented sensitivity.

Findings

Achieved a magnetic field sensitivity of 8.3 pT/Hz$^{1/2}$ over 120 μm$^2$ area.

Sensitivity close to the atom shot-noise limit, enabling quantum-enhanced measurements.

Potential for spatially resolved spin-squeezed magnetometry.

Abstract

We demonstrate a precision magnetic microscope based on direct imaging of the Larmor precession of a $^{87}$Rb spinor Bose-Einstein condensate. This magnetometer attains a field sensitivity of 8.3 pT/Hz$^{1/2}$ over a measurement area of 120 $\mu$m$^2$, an improvement over the low-frequency field sensitivity of modern SQUID magnetometers. The corresponding atom shot-noise limited sensitivity is estimated to be 0.15 pT/Hz$^{1/2}$ for unity duty cycle measurement. The achieved phase sensitivity is close to the atom shot-noise limit suggesting possibilities of spatially resolved spin-squeezed magnetometry. This magnetometer marks a significant application of degenerate atomic gases to metrology.