Visualizing strongly focused 3D light fields in an atomic vapor

TL;DR

This paper demonstrates a novel method to visualize and analyze strongly focused 3D vector light fields by mapping their polarization components onto atomic states, enabling advanced quantum sensing techniques.

Contribution

It introduces a new approach to directly detect axial polarization components of 3D light fields using atomic vapor in the hyperfine Paschen-Back regime, revealing detailed vectorial light-matter interactions.

Findings

Confirmed the mapping between 3D vector light and atomic transition strength

Demonstrated detection of axial polarization component in focused radial light

Analyzed effects of various polarization states on atomic absorption profiles

Abstract

Structured light, when strongly focused, generates highly confined vectorial electromagnetic field distributions which may feature a polarization component along the optical axis. Manipulating and detecting such 3D light fields is challenging, as conventional optical elements and detectors do not interact with the axial polarization component. Vector light can, however, be mapped onto atomic polarizations, making electric dipole transitions an ideal candidate to sense such 3D light configurations. Working in the hyperfine Paschen-Back regime, where the electric dipole transitions are spectrally resolved, we demonstrate direct evidence of the axial polarization component of strongly focused radial light. We investigate the influence of various input polarization states, including radial, azimuthal, and higher-order optical vortices, on atomic absorption profiles. Our results confirm a clear mapping between the 3D vector light and the atomic transition strength. This work provides new insights into vectorial light-matter interaction, and opens avenues for novel quantum sensing applications.