Experiments and theory on the quantum hall effect with inhomogeneous electron density

Abstract

Magnetotransport in a two-dimensional electron gas in the quantum Hall regime is calculated numerically using a local resistivity tensor. Landau level broadening and enhanced spin-splitting are taken into account, but the effects of localization are neglected. These calculations show that fluctuations in the electron density over a sample can lead to plateaus in the Hall resistance and broad minima in the magnetoresistance. Our calculations are compared with experiments for a simple Hall bar geometry as well as for two parallel Hall bars with their contacts connected by metal wires.