Supplemental Material for Comment on "Excitons in Molecular Aggregates with Levy Disorder: Anomalous Localization and Exchange Broadening of Optical Spectra", Phys.Rev.Lett. 109, 259701 (https://arxiv.org/abs/1208.2779)

TL;DR

This paper refutes a recent claim that heavy-tailed Levy disorder causes anomalous exciton localization and spectral broadening in molecular aggregates, asserting existing theory sufficiently explains these phenomena.

Contribution

It demonstrates that the previously established theory remains valid and can account for the observed properties without invoking new localization mechanisms.

Findings

Existing theory explains absorption band properties

No need for chain segmentation explanation

Heavy-tailed disorder does not alter localization mechanisms

Abstract

In their Letter "Excitons in Molecular Aggregates with Levy Disorder: Anomalous Localization and Exchange Broadening of Optical Spectra", Eisfeld et al. predicted the existence of exchange broadening and blue-shift of the absorption band and a non-universal disorder scaling of the localisation length of absorption band excitons in J-aggregates with heavy-tailed disorder, which they contrasted with the previously analysed Gaussian and Lorentzian case. The observations were explained by another localisation mechanism, the chain segmentation by outliers in heavy tails of the disorder distribution. We argue that the previously known theory does not break down and consequently anticipates the properties of the absorption band investigated in the commented work.