Effects of finite electric field and inelastic scattering on Anderson localization in two dimensions

Abstract

The localization range of electronic states in weakly disordered two-dimensional systems is first shown to be enhanced at zero temperature in the presence of an applied electric field. The enhancement factor, being proportional to the square of the range itself as well as to the square of the field strength, will be significant and sensitive to the applied field when the range itself becomes large, which is expected to be the case for two-dimensional disordered metallic systems. An explicit expression for the critical-field strength for the destruction of localization is also derived. The effect of inelastic scattering is then taken into account, extending the previously obtained results to finite temperatures. Any amount of inelastic collision is shown to be equivalent to an additional amount of the applied field, the increase being proportional to the inelastic scattering rate. The maximum allowable inelastic rate for localization is also given.