Cavity enhanced atomic magnetometry

TL;DR

This paper introduces a cavity-enhanced atomic magnetometer using conventional spherical vapor cells with internal coatings, achieving higher sensitivity than traditional single-pass setups for precision magnetic field measurements.

Contribution

It presents a novel all-optical magnetometry scheme that combines cavity enhancement with coated spherical vapor cells, simplifying design and improving sensitivity.

Findings

Increased optical polarization rotation with cavity enhancement

Longer spin coherence times due to coated spherical cells

Improved sensitivity over single-pass configurations

Abstract

Atom sensing based on Faraday rotation is an indispensable method for precision measurements, universally suitable for both hot and cold atomic systems. Here we demonstrate an all-optical magnetometer where the optical cell for Faraday rotation spectroscopy is augmented with a low finesse cavity. Unlike in previous experiments, where specifically designed multipass cells had been employed, our scheme allows to use conventional, spherical vapour cells. Spherical shaped cells have the advantage that they can be effectively coated inside with a spin relaxation suppressing layer providing long spin coherence times without addition of a buffer gas. Cavity enhancement shows in an increase in optical polarization rotation and sensitivity compared to single-pass configurations.