Interaction of vector light beams with atoms exposed to a time-dependent magnetic field

TL;DR

This paper extends atomic absorption-based magnetic field sensing techniques to oscillating fields, demonstrating through theoretical analysis that absorption profiles are sensitive to both the strength and frequency of such fields, enabling advanced diagnostics.

Contribution

It introduces a theoretical framework for detecting oscillating magnetic fields using atomic absorption profiles, expanding previous static field methods.

Findings

Absorption profiles are sensitive to the amplitude and frequency of oscillating magnetic fields.

Theoretical analysis confirms the feasibility of using this method for dynamic magnetic field diagnostics.

Detailed calculations for rubidium atoms demonstrate practical applicability.

Abstract

During recent years interest has been rising for applications of vector light beams towards magnetic field sensing. In particular, a series of experiments were performed to extract information about properties of static magnetic fields from absorption profiles of light passing through an atomic gas target. In the present work, we propose an extension to this method for oscillating magnetic fields. To investigate this scenario, we carried out theoretical analysis based on the time-dependent density matrix theory. We found that absorption profiles, even when averaged over typical observation times, are indeed sensitive to both strength and frequency of the time-dependent field, thus opening the prospect for a powerful diagnostic technique. To illustrate this sensitivity, we performed detailed calculations for the $5s \;\, {}^2S_{1/2}$ ($F=1$) $-$ $5p \;\, {}^2 P_{3/2}$ ($F=0$) transition in rubidium atoms, subject to a superposition of an oscillating (test) and a static (reference) magnetic field.