Deflection of Slow Light by Magneto-Optically Controlled Atomic Media

TL;DR

This paper develops a semi-classical theory explaining how slow light can be deflected in atomic media with inhomogeneous magnetic or control fields, aligning with recent experiments and predicting new deflection effects.

Contribution

It introduces a theoretical framework based on Fermat's principle for light deflection in atomic media with spatially varying parameters, explaining recent observations and predicting novel effects.

Findings

Consistent explanation of recent experimental light deflection results.

Prediction of new deflection phenomena under inhomogeneous control laser fields.

Theoretical demonstration of slow light manipulation in atomic media.

Abstract

We present a semi-classical theory for light deflection by a coherent $\Lambda$-type three-level atomic medium in an inhomogeneous magnetic field or an inhomogeneous control laser. When the atomic energy levels (or the Rabi coupling by the control laser) are position-dependent due to the Zeeman effect by the inhomogeneous magnetic field (or the inhomogeneity of the control field profile), the spatial dependence of the refraction index of the atomic medium will result in an observable deflection of slow signal light when the electromagnetically induced transparency happens to avoid medium absorption. Our theoretical approach based on Fermat's principle in geometrical optics not only provides a consistent explanation for the most recent experiment in a straightforward way, but also predicts the new effects for the slow signal light deflection by the atomic media in an inhomogeneous off-resonant control laser field.