Density of States in Landau Level Tails of GaAs-AlxGa1-xAs Heterostructures

Abstract

From an analysis of the thermally activated resistivity as a function of the magnetic field in the quantum Hall regime we deduced the position of the Fermi energy in the mobility gap as a function of the filling factor and therefore the density of states. The measured density of states is best described by a Gaussian like profile superimposed on a constant background.