Anisotropic disorder in high-mobility 2D heterostructures and its correlation to electron transport

Surface morphology of high-Mobility heterostructures. is examined and correlated with dc transport. All samples examined show evidence of lines in the [1 (1) over bar0] direction with roughness ranging from small-amplitude features to severe anisotropic ridges. Transport in these samples iis consistent with that in samples having artificially induced 1D charge modulations. The native surface properties reflect a prevalent, anisotropic disorder affecting 2D electron conduction. Importantly the native lines are orthogonal to the stripes theoretically proposed to explain high Landau level transport anisotropies.