All optical sensor for automated magnetometry based on Coherent Population Trapping

TL;DR

This paper presents an all-optical, remote magnetometer based on Coherent Population Trapping in Cs atoms, achieving high sensitivity for long-term magnetic field measurements with minimized perturbations.

Contribution

The work introduces a fully optical, remote sensing magnetometer utilizing CPT with detailed analysis of resonance parameters for enhanced sensitivity.

Findings

Achieved high sensitivity in magnetic field detection.

Demonstrated remote sensing capability via optical fiber.

Optimized CPT resonance parameters for stable measurements.

Abstract

An automated magnetometer suitable for long lasting measurement under stable and controllable experimental conditions has been implemented. The device is based on Coherent Population Trapping (CPT) produced by a multi-frequency excitation. CPT resonance is observed when a frequency comb, generated by diode laser current modulation, excites Cs atoms confined in a $\pi/4\times(2.5)^2\times1 \textrm{cm}^3$, 2 Torr $N_2$ buffered cell. A fully optical sensor is connected through an optical fiber to the laser head allowing for truly remote sensing and minimization of the field perturbation. A detailed analysis of the CPT resonance parameters as a function of the optical detuning has been made in order to get high sensitivity measurements. The magnetic field monitoring performances and the best sensitivity obtained in a balanced differential configuration of the sensor are presented.