Heterostructure Symmetry and the Orientation of the Quantum Hall Nematic Phases

ORAL

Abstract

The native symmetry-breaking potential which consistently orients the quantum Hall nematic phases in high mobility 2D electron systems relative to the host semiconductor crystal axes remains unknown. Here we report an extensive set of measurements examining the role of the structural symmetries of the potential confining the 2D system in determining the orientation of the nematics [1]. In single quantum well samples we find that neither the local symmetry of the confinement potential nor the depth of the 2D electron system beneath the sample surface dictates the orientation of the nematic. In contrast, for 2D electrons confined at a single heterointerface between GaAs and AlGaAs, the nematic orientation does depends on the depth of the 2D electron system beneath the sample surface. We relate these results to various theoretical models of the symmetry-breaking potential. [1] J. Pollanen et al., Phys. Rev B 92, 115410 (2015).

*Supported by the Institute for Quantum Information and Matter, a NSF Physics Frontiers Center (NSF Grant PHY-1125565) and the Gordon and Betty Moore Foundation via grant GBMF-12500028 and EPiQS Grant GBMF4420, and by NSF MRSEC Grant DMR-1420541.

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Authors

  • J. P. Eisenstein

    • Institute for Quantum Information and Matter and Dept. of Physics, Caltech, Pasadena, CA
    • Institute for Quantum Information and Matter and Department of Physics, California Institute of Technology, Pasadena, California 91125, USA

  • J. Pollanen

    • Institute for Quantum Information and Matter and Department of Physics, California Institute of Technology, Pasadena, California 91125, USA
    • Institute for Quantum Information and Matter and Dept. of Physics, Caltech, Pasadena, CA

  • K.B. Cooper

    • Institute for Quantum Information and Matter and Dept. of Physics, Caltech, Pasadena, CA

  • S. Brandsen

    • Institute for Quantum Information and Matter and Dept. of Physics, Caltech, Pasadena, CA

  • Loren Pfeiffer

    • Princeton University
    • Dept. of Electrical Engineering, Princeton University, Princeton, NJ
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544
    • Department of Electrical Engineering, Princeton University
    • Princeton

  • Ken West

    • Princeton University
    • Dept. of Electrical Engineering, Princeton University, Princeton, NJ
    • Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544
    • Princeton