Theory of non-equilibrium diffusive transport in disordered materials

Abstract

A new method has been developed to study non-equilibrium transport and energy relaxation phenomena in disordered organic and inorganic semiconductors. Given a distribution of localized states, the mean-square displacement and average energy of the excitation may be evaluated as functions of initial energy and time.

The theory has a wide range of possible applications, for example to exciton and carrier transport in disordered organic and inorganic semiconductors. In disordered organic semiconductors, the density of excited states is usually well described by a Gaussian model. Current and energy relaxation and temperature-dependent mobilities have been studied for this Gaussian model using Monte-Carlo simulations. The theoretical results are found to be in excellent agreement with those of the simulations.