Negative Magnetoresistance in the Anderson Localized States

Abstract

It is shown that the mechanism of the electronic conduction due to variable-range hopping in the Anderson localized states gives rise to a large negative magnetoresistance, particularly in the vicinity of the metal-nonmetal transition. This result is mainly caused by an exponential dependence of the hopping rate on the highest occupied energy levels. The same mechanism also leads to a strong electric field-dependence of the conductivity.