Field-tilt Anisotropy Energy in Quantum Hall Stripe States
Abstract
Recently reported giant anisotropy in the longitudinal resistivity of a 2D electron system with valence Landau level index
N≥2
has been interpreted as a signal of unidirectional charge density wave (UCDW) ground states. We report on detailed Hartree-Fock calculations of the UCDW orientation energy induced by a tilted magnetic field. We find that for current experimental samples stripes are oriented perpendicular to the in-plane field, consistent with experiment. For wider 2D electron systems we predict tilt-induced stripe states with variable anisotropy energy sign.