Anisotropic Fermi Contour of (001) GaAs Electrons in Parallel Magnetic Fields

ORAL

Abstract

We demonstrate a severe Fermi contour anisotropy induced by the application of a parallel magnetic field to high-mobility electrons confined to a 30-nm-wide (001) GaAs quantum well. We study commensurability oscillations, namely geometrical resonances of the electron orbits with a unidirectional, surface-strain-induced, periodic potential modulation, to directly probe the size of the Fermi contours along and perpendicular to the parallel field. Their areas are obtained from the Shubnikov-de Haas oscillations. Our experimental data agree semi-quantitatively with the results of parameter-free calculations of the Fermi contours but there are significant discrepancies.

*We acknowledge support through the DOE BES, the Gordon and Betty Moore Foundation, Keck Foundation, NSF, and MRSEC. A portion of this work was performed at the National High Magnetic Field Laboratory.

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Authors

  • M.A. Mueed

    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA

  • Dobromir Kamburov

    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA

  • Mansour Shayegan

    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
    • Princeton Univ

  • L.N. Pfeiffer

    • Princeton University
    • Princeton Univ
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
    • Department of Electrical Engineering, Princeton University

  • K.W. West

    • Princeton University
    • Princeton Univ
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA

  • Kirk Baldwin

    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
    • Princeton Univ
    • Princeton University

  • J.J.D. Lee

    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA

  • Roland Winkler

    • Department of Physics, Northern Illinois University, DeKalb, Illinois 60115, USA