Nanotesla-level, shield-less, field-compensation-free, wave-mixing-enhanced body-temperature atomic magnetometry for biomagnetism

TL;DR

This paper introduces a novel atomic magnetometry technique that achieves nanotesla-level detection of magnetic fields at body temperature without shielding or complex compensation, enabling potential biomedical applications.

Contribution

The authors develop an optical inelastic-wave-mixing-enhanced atomic magnetometry method that significantly improves sensitivity without traditional shielding or compensation.

Findings

Over 300,000-fold enhancement of magneto-optical rotation signal

Detects magnetic fields at nanotesla levels at body temperature

Potential for clinical biomagnetic imaging

Abstract

We report an optical inelastic-wave-mixing-enhanced atomic magnetometry technique that results in nT-level magnetic field detection at temperatures compatible with the human body without magnetic shielding, zero-field compensation, or high-frequency modulated phase-locking spectroscopy. Using Gaussian magnetic pulses that mimic the transient magnetic field produced by an action potential on a frog's nerve, we demonstrate more than 300,000-fold (550-fold) enhancement of magneto-optical rotation signal power spectral-density (power amplitude) over the conventional single-beam $\Lambda-$scheme atomic magnetometry method. This new technique may bring possibilities for extremely sensitive magnetic field imaging of biological systems accessible via an optical fiber in clinical environments.