Conductivity tensor of striped quantum Hall phases

We study the transport properties of pinned striped quantum Hall phases. We show that, under quite general assumptions, the macroscopic conductivity t ensor satisfies a semicircle law. In particular, this result is valid for b oth smectic and nematic stripe phases, independent of the presence of topol ogical and orientational defects such as dislocations and grain boundaries. As a special case, our results explain the experimental validity of a prod uct rule for the dissipative part of the resistivity tensor, which was prev iously derived by MacDonald and Fisher (cond-mat/9907278) for a perfect str ipe structure.