Magnetometry using sodium fluorescence with synchronous modulation of two-photon resonant light fields

TL;DR

This paper introduces a novel sodium fluorescence magnetometry technique using synchronous modulation of two-photon resonant light fields, demonstrating high sensitivity and potential for remote magnetic field measurements.

Contribution

The paper presents a new method for magnetic resonance generation with synchronous two-photon light modulation, including a theoretical model and experimental validation for sodium-based remote magnetometry.

Findings

Achieved magnetic field sensitivity of 41 pT/√Hz.

Observed a secondary resonance at 3Ω_L for magnetic field orientation detection.

Demonstrated the technique's effectiveness in sodium fluorescence measurements.

Abstract

We report a new technique for generating magnetic resonance with synchronous modulation of two-photon resonant light fields. Magnetic resonances in fluorescence from a sodium cell are measured to demonstrate suitability of this technique for remote magnetometry. A strong magnetic resonance with its dip corresponding to the Larmor frequency is produced in the presence of a transverse magnetic field. An additional resonance at 3\{Omega_L} is observed, which can be used to determine the magnetic field orientation. We have developed a theoretical model based on the density matrix equations to verify our experimental observations. An average magnetic field sensitivity of 41 \mathbf{pT}/\sqrt{\mathbf{Hz}} is measured using light duty cycles ranging from 35% to 10%. We have discussed possible changes that can be made to improve the sensitivity of this scheme further.