Disordered quantum smectics

We study the impurity pinning of the Quantum Hall (QH) smectic state arising in two-dimensional electron systems in high Landau levels. We use replicas and a Gaussian Variational method to deal with the disorder. The pinned quantum smectic exhibits very anisotropic behaviour, with width correlations along the stripes manifesting a power law behavior. We calculate the dynamical conductivity $\sigma_{xx} (\bm{q},\omega)$ along the stripe direction and find a $\bm{q}$-dependent pinning peak