Isotropically conducting (hidden) quantum Hall stripe phases in a two-dimensional electron gas

Quantum Hall stripe (QHS) phases, predicted by the Hartree-Fock theory, are manifested in GaAs-based two-dimensional electron gases as giant resistance anisotropies. Here, we predict a "hidden" QHS phase which exhibits isotropic resistivity whose value, determined by the density of states of QHS, is independent of the Landau index N and is inversely proportional to the Drude conductivity at zero magnetic field. At high enough N, this phase yields to an Ando-Unemura/Coleridge-Zawadski-Sachrajda phase in which the resistivity is proportional to 1/N and to the ratio of quantum and transport lifetimes. Experimental observation of this border can provide an alternative way to obtain quantum relaxation time.