Nonlocal correlations of the local density of states in disordered quantum Hall systems
arXiv:1012.3128 · doi:10.1103/PhysRevB.83.125321
Abstract
Motivated by recent high-resolution scanning tunneling microscopy (STM) experiments in the quantum Hall regime both on massive two-dimensional electron gas and on graphene, we consider theoretically the disorder averaged nonlocal correlations of the local density of states (LDoS) for electrons moving in a smooth disordered potential in the presence of a high magnetic field. The intersection of two quantum cyclotron rings around the two different positions of the STM tip, correlated by the local disorder, provides peaks in the spatial dispersion of the LDoS-LDoS correlations when the intertip distance matches the sum of the two quantum Larmor radii. The energy dependence displays also complex behavior: for the local LDoS-LDoS average (i.e., at coinciding tip positions), sharp positive correlations are obtained for tip voltages near Landau level, and weak anticorrelations otherwise.
arXiv comment11 pages, 8 figures ; v2: 2 references added and small extension of conclusion, similar to published version
References in corpus (10)
- Anderson Transitions
- Observation of the e/3 Fractionally Charged Laughlin Quasiparticles
- Charge Density Wave in Two-Dimensional Electron Liquid in Weak Magnetic Field
- The Quantum Hall Transition in Real Space: From Localized to Extended States
- High magnetic field theory for the local density of states in graphene with smooth arbitrary potential landscapes
- Microscopics of disordered two-dimensional electron gases under high magnetic fields: Equilibrium properties and dissipation in the hydrodynamic regime
- Correlation-function spectroscopy of inelastic lifetime in heavily doped GaAs heterostructures
- Enhanced fluctuations of the tunneling density of states near bottoms of Landau bands measured by a local spectrometer
- Electron quantum dynamics in closed and open potentials at high magnetic fields: Quantization and lifetime effects unified by semicoherent states
- Density of states of a two-dimensional electron gas in a non-quantizing magnetic field