Anderson localization of light by impurities in a solid transparent matrix

TL;DR

This paper explores the potential for observing three-dimensional Anderson localization of light in solid transparent media with impurity atoms, addressing challenges like thermal oscillations and spectral broadening.

Contribution

It demonstrates that high impurity densities can overcome issues like broadening, making localization observable despite thermal and inhomogeneous effects.

Findings

High impurity densities mitigate inhomogeneous broadening.

Thermal oscillations have minimal impact on light propagation.

Localization is feasible with sufficient impurity concentration.

Abstract

A solid transparent medium with randomly positioned, immobile impurity atoms is a promising candidate for observation of Anderson localization of light in three dimensions. It can have low losses and allows for mitigation of the detrimental effect of longitudinal optical fields by an external magnetic field, but it has its own issues: thermal oscillations of atoms around their equilibrium positions and inhomogeneous broadening of atomic spectral lines due to random local electric fields. Our calculations suggest that these complications should not impede observation of Anderson localization of light in such materials provided that sufficiently high number densities of impurities can be reached. The thermal oscillations hardly affect light propagation whereas the inhomogeneous broadening can be compensated for by increasing the number density of impurities.