Local density of states in disordered two-dimensional electron gases at high magnetic field

Abstract

Motivated by high-accuracy scanning tunneling spectroscopy measurements on disordered two-dimensional electron gases in strong magnetic field, we present an exact solution for the local density of states (LDoS) of electrons moving in an arbitrary potential smooth on the scale of the magnetic length, that can be locally described up to its second derivatives. We use a technique based on coherent state Green's functions, allowing us to treat on an equal footing confining and open quantum systems. The energy-dependence of the LDoS is found to be universal in terms of local geometric properties, such as drift velocity and potential curvature. We also show that thermal effects are quite important close to saddle points, leading to an overbroadening of the tunneling trajectories.

4 pages, 3 figures ; typos corrected + one reference updated

References in corpus (4)

• The Quantum Hall Transition in Real Space: From Localized to Extended States
• Quantum transport properties of two-dimensional electron gases under high magnetic fields
• Microscopics of disordered two-dimensional electron gases under high magnetic fields: Equilibrium properties and dissipation in the hydrodynamic regime
• Electron quantum dynamics in closed and open potentials at high magnetic fields: Quantization and lifetime effects unified by semicoherent states