Fractional Quantum Hall Effect at $\nu = 1/2$ in Hole Systems Confined to GaAs Wide Quantum Wells

ORAL

Abstract

We observe fractional quantum Hall effect (FQHE) at the even-denominator Landau level filling factor $\nu = 1/2$ in two-dimensional hole systems confined to GaAs quantum wells of width 30 to 50 nm and having bilayer-like charge distributions. The $\nu = 1/2$ FQHE is stable when the charge distribution is symmetric and only in a range of intermediate densities, qualitatively similar to what is seen in two-dimensional electron systems confined to approximately twice wider GaAs quantum wells. Despite the complexity of the hole Landau level structure, originating from the coexistence and mixing of the heavy- and light-hole states, we find the hole $\nu = 1/2$ FQHE to be consistent with a two-component, Halperin-Laughlin ($\Psi_{331}$) state.

*We acknowledge support through the DOE BES (DE-FG02-00-ER45841) for measurements, and the Gordon and Betty Moore Foundation (Grant GBMF2719), Keck Foundation, and the NSF (DMR-0904117, DMR-1305691 and MRSEC DMR-0819860) for sample fabrication. Work at Arg

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Authors

  • Sukret Hasdemir

    • Princeton Univ
    • Princeton University

  • Yang Liu

    • Princeton Univ
    • Princeton University

  • Aurelius Graninger

    • Princeton Univ

  • 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

  • Roland Winkler

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