Magnetotransport through antidot and dot lattices in two-dimensional structures

Abstract

The redistribution of electron density caused by magnetic gaps is explored for both dot and antidot lattices. It is assumed that the saddle points in the electron-density distribution determine the magnetotransport in these periodic systems. We show that the quantum Hall plateaus are shifted to lower magnetic fields in the case of antidot lattices and to higher magnetic fields in the case of dot lattices. Our theory is in a good quantitative agreement with the experimental data by Ensslin and Petroff for antidot systems. The results are obtained by computer simulation taking into account nonlinear screening by the electrons of two Landau levels. For one-level screening, we present an analytical solution of the nonlinear electrostatic problem