CURRENT RELAXATION IN DISORDERED ONE-DIMENSIONAL AND 2-DIMENSIONAL SYSTEMS

The current relaxation of disordered one- and two-dimensional systems is treated on the basis of a self-consistent approach for the diffusio n coefficient. At the predicted delocalization field strength a long-t ime power law decay of the current is observed according to j(t) congr uent-to t-1/2 if inelastic scattering processes are neglected. This sl ow current relaxation should be measurable in one-dimensional systems. The experimental verification of the results for a two-dimensional el ectron gas is complicated on account of the fact that both the delocal ization field strength and the characteristic decay time depend expone ntially on the disorder parameter. The measurement of the slow 2D curr ent relaxation requires very low carrier densities and extremely low t emperatures.