Basis and applications of isothermal averaging in transport at low and high electric fields

Abstract

The basis for the applicability of isothermal response theory for electronic transport in a disordered system without Coulomb repulsions in a static applied electric field is discussed. The results of this method for the conductivity in the lowest order of perturbation theory (weak localization) are calculated and found to be in agreement with those obtainable by the usual approach based on the Kubo formula. It is found that the method can also predict localization and give a fair description of hopping processes and high-field behaviour.