Ballistic transport of (001) GaAs 2D holes through a strain-induced   lateral superlattice
  We report the observation of ballistic commensurability oscillations and positive magnetoresistance in a high-mobility, (001) GaAs two-dimensional hole system with a unidirectional, surface-strain-induced, periodic potential modulation. The positions of the resistivity minima agree well with the electrostatic commensurability condition. From an analysis of the amplitude of the oscillations we deduce a ballistic scattering time and an effective magnitude for the induced periodic potential seen by the two-dimensional holes. 
D. Kamburov, H. Shapourian, M. Shayegan, L. N. Pfeiffer, K. W. West,   K. W. Baldwin, R. Winkler
cond-mat.mes-hall