Linear optical properties of one-dimensional Frenkel exciton systems with intersite energy correlations

TL;DR

This paper investigates how intersite energy correlations influence the linear optical properties of one-dimensional disordered Frenkel exciton systems, revealing complex behaviors in absorption and radiative enhancement.

Contribution

It provides a theoretical analysis of the impact of energy correlations on optical properties, explaining experimental observations with a focus on exciton localization.

Findings

Absorption linewidth approaches disorder level with increasing correlation.

Radiative rate enhancement exhibits a non-monotonous trend.

Theoretical results align well with recent experimental data.

Abstract

We analyze the effects of intersite energy correlations on the linear optical properties of one-dimensional disordered Frenkel exciton systems. The absorption line width and the factor of radiative rate enhancement are studied as a function of the correlation length of the disorder. The absorption line width monotonously approaches the seeding degree of disorder on increasing the correlation length. On the contrary, the factor of radiative rate enhancement shows a non-monotonous trend, indicating a complicated scenario of the exciton localization in correlated systems. The concept of coherently bound molecules is exploited to explain the numerical results, showing good agreement with theory. Some recent experiments are discussed in the light of the present theory.