Excitons in Molecular Aggregates with L\'evy Disorder: Anomalous Localization and Exchange Broadening of Optical Spectra

TL;DR

This paper predicts novel optical line broadening and localization behaviors in molecular aggregates with heavy-tailed Le9vy disorder, highlighting nonuniversal scaling and divergence from traditional models with finite second moments.

Contribution

It introduces the effects of Le9vy disorder on exciton localization and optical spectra, revealing phenomena absent in models with finite second moments.

Findings

Exchange broadening of optical lineshapes predicted

Nonuniversal disorder scaling of exciton localization

Relevance to other collective excitations

Abstract

We predict the existence of exchange broadening of optical lineshapes in disordered molecular aggregates and a nonuniversal disorder scaling of the localization characteristics of the collective electronic excitations (excitons). These phenomena occur for heavy-tailed L\'evy disorder distributions with divergent second moments - distributions that play a role in many branches of physics. Our results sharply contrast with aggregate models commonly analyzed, where the second moment is finite. They bear a relevance for other types of collective excitations as well.