Hopping charge transport in amorphous organic and inorganic materials with spatially correlated random energy landscape

Abstract: General properties of the hopping transport of charge carriers in amorphous organic and inorganic materials are discussed. We consider the case where the random energy landscape in the materials is strongly spatially correlated. This is a very typical situation in the organic materials having the Gaussian density of states (DOS) and may be realized in some materials with the exponential DOS. We demonstrate that the different type of DOS leads to a very different functional form of the mobility field dependence even in the case of the identical correlation function of random energy. We provide important arguments in favor of the significant contribution of the local orientational order to the total magnitude of the energetic disorder in organic materials. A simple but promising model of charge transport in highly anisotropic composites materials is suggested.