Finite Temperature Density Instability at High Landau Level Occupancy

We study here the onset of charge density wave instabilities in quantum Hall systems at finite temperature for Landau level filling $\nu>4$. Specific emphasis is placed on the role of disorder as well as an in-plane magnetic field. Beyond some critical value, disorder is observed to suppress the charge density wave melting temperature to zero. In addition, we find that an in-plane magnetic field orients the stripes along the direction of the field. In conjunction with the experiments, our findings imply that if stripes exist in the experimental systems, then the most conducting direction is perpendicular to the stripes. The implications of this result are discussed.