Optical absorption in paired correlated random lattices

TL;DR

This paper investigates how paired correlated disorder affects optical absorption spectra in a one-dimensional lattice, revealing characteristic spectral lines and providing analytical tools to interpret experimental data.

Contribution

It introduces a detailed analysis of paired correlated disorder effects on optical absorption and derives an analytical expression linking spectral features to model parameters.

Findings

Paired correlation creates distinct absorption lines.

Absorption line behavior varies with defect concentration.

Analytical expression relates spectral features to disorder parameters.

Abstract

Optical absorption in a random one-dimensional lattice in the presence of paired correlated disorder is studied. The absorption line shape is evaluated by solving the microscopic equations of motion of the Frenkel-exciton problem in the lattice. We find that paired correlation causes the occurrence of well-defined characteristic lines in the absorption spectra which clearly differ from the case of unpaired correlation. The behavior of the absorption lines as a function of defect concentration is studied in detail. We also show how exciton dynamics can be inferred from experimental data by deriving an analytical expression relating the energy and intensity of lines to the model parameters.