Non-linear Transport in Quantum-Hall Smectics

Recent transport experiments have established that two-dimensional electron systems with high-index partial Landau level filling, ν∗ = ν − [ν], have ground states with broken orientational symmetry. In a mean-field theory, the broken symmetry state consists of electron stripes with local filling factor [ν] + 1, separated by hole stripes with filling factor [ν]. We have recently developed a theory of these states in which the electron stripes are treated as one-dimensional electron systems coupled by interactions and described by using a Luttinger liquid model. Among other things, this theory predicts non-linearities of opposite sign in easy and hard direction resistivities. In this article we briefly review our theory, focusing on its predictions for the dependence of non-linear transport exponents on the separation d between the twodimensional electron system and a co-planar screening layer.