A new temperature-dependent magneto-conductance in a disordered electron gas

Abstract
Using long-channel GaAs MESFET structures doped in excess of the Mott criterion, the authors have measured the inelastic length in a 2DEG by two methods, the parallel and perpendicular magnetoresistance. The low-field data were fitted using the theories of Altshuler and Aronov (1981) and of Hikami et al. (1980). The two techniques were found to give good agreement. However, high parallel magnetic field data show a conductivity correction going as delta sigma approximately=B12/ln T, a result not predicted by existing theories. The authors present a model for this effect which gives good agreement with experiment.