Orientational Effects on the Amplitude and Phase of Polarimeter Signals in Double Resonance Atomic Magnetometry

TL;DR

This paper investigates how the orientation of static magnetic fields affects the amplitude and phase of signals in double resonance atomic magnetometry, providing both theoretical models and experimental data.

Contribution

It introduces a detailed model of polarimeter signals considering atomic alignment evolution and presents comprehensive experimental measurements over all orientations.

Findings

Signal amplitude and phase depend strongly on magnetic field orientation.

The study provides a complete angular distribution of signal parameters.

Experimental data confirms the theoretical model.

Abstract

Double resonance optically pumped magnetometry can be used to measure static magnetic fields with high sensitivity by detecting a resonant atomic spin response to a small oscillating field perturbation. Determination of the resonant frequency yields a scalar measurement of static field ($B_0$) magnitude. We present calculations and experimental data showing that the on-resonance polarimeter signal of light transmitted through an atomic vapour in arbitrarily oriented $B_0$ may be modelled by considering the evolution of alignment terms in atomic polarisation. We observe that the amplitude and phase of the magnetometer signal are highly dependent upon $B_0$ orientation, and present precise measurements of the distribution of these parameters over the full 4{\pi} solid angle.