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Magnetotransport in a Two-Dimensional Electron Gas Subject to a Weak Superlattice Potential

  • R. R. Gerhardts
  • D. Pfannkuche
  • D. Weiss
  • U. Wulf
Part of the Springer Series in Solid-State Sciences book series (SSSOL, volume 101)

Abstract

We present experimental and theoretical results on commensurability oscillations of the magnetoresistivity in high-mobility two-dimensional electron systems subject to a weak superlattice potential. Experimentally, the band conductivity of a sample with a hologra-phically produced square-grid potential is shown to be considerably smaller than that of the same sample with a similar linear grating potential of the same lattice constant. This is explained by a magnetotransport theory with due consideration of collision broadening effects and the peculiar subband splitting of Landau levels resulting in a Hofstadter-type energy spectrum.

Keywords

Band Conductivity Landau Level Flat Band Perpendicular Magnetic Field Grid Modulation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1992

Authors and Affiliations

  • R. R. Gerhardts
    • 1
  • D. Pfannkuche
    • 1
  • D. Weiss
    • 1
  • U. Wulf
    • 1
  1. 1.Max-Planck-Institut für FestkörperforschungStuttgart 80Germany

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