Exciton migration in a fluctuating medium I

Abstract

Abstract A statistical mechanical theory of exciton migration in a fluctuating environment is developed with the use of the time-convolutionless equation formalism. This gives a satisfactory result when the stochastic perturbations acting on excitons are assumed to be Gaussian. Our theory is valid for any timescale and is applicable to the case of off-diagonal randomness as well as the diagonal randomness. For the Gaussian-Markoffian process, a basic equation can be solved analytically to give optical absorption spectra and the density of states. These quantities show systematic variations when certain characteristic parameters are changed.