Density of States of Landau Levels in Two-Dimensional Systems from Activated Transport, Magnetocapacitance and Gate Current Experiments

Abstract

In this publication we demonstrate that a combination of capacitance and gate current experiments together with an analysis of thermally activated conductivity seems to be useful for the determination of the density of states (DOS) of Landau levels in two-dimensional systems. The experimental results suggest a Landau level width not far away from the predictions of the self-consistent Born approximation (SCBA) if the Fermi level is close to the center of a Landau level. The DOS between Landau levels however cannot be explained with such a narrow linewidth and the experiments suggest the existence of a background DOS or an increased linewidth broadening for integer filling factors.