Spatial correlations of the spontaneous decay rate as a probe of dense and correlated disordered materials

TL;DR

This paper introduces a new spatial correlation function for wave decay rates in disordered media, revealing how it encodes structural and local environmental information, potentially advancing imaging and sensing technologies.

Contribution

It defines and analyzes a novel correlation function for decay rates, linking it to medium structure and local environment, with implications for imaging and sensing.

Findings

The amplitude and width of $C_{ extGamma}$ provide independent information.

$C_{ extGamma}$ can distinguish structural correlations from local environment effects.

Potential applications in imaging and sensing in complex media.

Abstract

We study theoretically and numerically a new kind of spatial correlation for waves in disordered media. We define $C_{\Gamma}$ as the correlation function of the fluorescent decay rate of an emitter at two different positions inside the medium. We show that the amplitude and the width of $C_{\Gamma}$ provide decoupled information on the structural correlation of the disordered medium and on the local environment of the emitter. This result may stimulate the emergence of new imaging and sensing modalities in complex media.