Microscopic details of stripes and bubbles in the quantum Hall regime

Abstract

We use a fully self-consistent laterally resolved Hartree-Fock approximation for numerically addressing the electron configurations at higher Landau levels in the quantum Hall regime for near-macroscopic sample sizes. At low disorder we find spatially resolved, stripe- and bubblelike charge-density modulations and show how these emerge depending on the filling factor. The microscopic details of these boundary regions determine the geometrical boundary conditions for aligning the charge-density modulation either as stripes or bubbles. Transport is modeled using a nonequilibrium network model giving a pronounced anisotropy in the direction of the injected current in the stripe regime close to half filling. We obtain a stripe period of 2.9 cyclotron radii. Our results provide an intuitive understanding of its consequences in strong magnetic fields and indicate the dominance of many particle physics in the integer quantum Hall regime.