We study two-dimensional interacting electrons in a weak perpendicular magnetic field with the filling factor ν≫1 and in the presence of a quenched disorder. As it is known, the unidirectional charge density wave state can exist near a half-filled high Landau level at low temperatures if disorder is weak enough. We show that the existence of the unidirectional charge density wave state at temperature T<Tc where Tc is the transition temperature leads to the anisotropic conductivity tensor. We find that the anisotropic part of conductivity tensor is proportional to (Tc−T)/Tc below the transition in accordance with the experimental findings. The order parameter fluctuations wash out the mean-field cusp at T=Tc and the conductivity tensor becomes anisotropic even above the mean-field transition temperature Tc.
@article{arxiv.cond-mat/0405162,
title = {Anisotropic conductivity tensor on a half-filled high Landau level},
author = {I. S. Burmistrov},
journal= {arXiv preprint arXiv:cond-mat/0405162},
year = {2007}
}