Temperature-induced transport asymmetry around half-filling in high Landau levels

ORAL

Abstract

We report a temperature dependence study of transport properties in an ultra-low disorder GaAs two-dimensional electron system around half-filling of the N = 2 Landau level. In this study, we performed measurements of both the zero-bias magnetoresistance Rxx and the differential resistance dVxx/dI along the hard transport direction around filling factor ν = 9/2 at different temperatures. At high temperature, T = 100 mK, both Rxx and dVxx/dI are symmetric around ν = 9/2. However, as temperature is decreased towards T = 10 mK both Rxx and dVxx/dI become asymmetric: the Rxx peak shifts to lower magnetic field away from exact half-filling, and dVxx/dI shows strong non-linearity on the high field side of the Rxx peak. Our data suggests that a temperature induced breakdown of particle-hole symmetry occurs at low temperatures. At high temperature T = 100 mK where the system behaves as a standard anisotropic nematic, particle-hole symmetry is restored.

*This work was supported by the Department of Energy, Office of Basic Energy Sciences, under Award number DE-SC0006671. Additional support for sample growth from the W. M. Keck Foundation and Microsoft Station Q is gratefully acknowledged.

–

Presenters

  • Qi Qian

    • Physics, Purdue University
    • Purdue University
    • Purdue Univ

Authors

  • Qi Qian

    • Physics, Purdue University
    • Purdue University
    • Purdue Univ

  • James Nakamura

    • Physics, Purdue University
    • Purdue Univ

  • Michael Yannell

    • Purdue Univ

  • Saeed Fallahi

    • Purdue Univ

  • Geoffrey Gardner

    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Microsoft Station Q Purdue
    • Birck Nanotechnology Center, Purdue University
    • Purdue University, Station Q Purdue
    • Purdue Univ
    • Purdue University
    • Physics and Astronomy, Purdue University

  • Michael Manfra

    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Department of Physics and Astronomy and Microsoft Station Q Purdue, Purdue University
    • Purdue University
    • Physics, Purdue University
    • Purdue University, Station Q Purdue
    • Purdue Univ
    • Department of Physics and Astronomy, and School of Materials Engineering, and School of Electrical and Computer Engineering, Purdue University
    • Physics and Astronomy, Purdue University
    • Dept. of Physics and Astronomy, Purdue Univ