Fractional Quantum Hall Effect in AlAs 2D Electrons

ORAL

Abstract

We study two-dimensional (2D) electrons confined to an AlAs quantum well, with density n = 1.5 x 1011 cm-2 and unprecedented high mobility, 106 cm2V-1s-1. The 2D electrons in this system occupy conduction-band minima (valleys) with anisotropic dispersion and effective mass. The magneto-resistance traces exhibit a rich sequence of fractional quantum Hall states near filling factor ν = ½, up to high-order fractions 8/15 and 8/17. We study the temperature dependence of these states, and extract energy gaps and composite fermion effective masses. We compare these with the relevant parameters in other 2D systems such as 2D electrons confined to GaAs quantum wells.

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Presenters

  • Kevin Villegas Rosales

    Princeton Univ

Authors

  • Kevin Villegas Rosales

    Princeton Univ

  • Edwin Chung

    Princeton Univ, EE, Princeton University

  • Hao Deng

    Princeton Univ, Electrical Engineering, Princeton Univ

  • K Baldwin

    Princeton University, Princeton Univ, Electrical Engineering, Princeton Univ, Department of Electrical Engineering, Princeton University, EE, Princeton University

  • K West

    Electrical Engineering, princeton university, Department of Electrical Engineering, Princeton University, Princeton University, Univ of Basel, Princeton Univ, Electrical Engineering, Princeton Univ, EE, Princeton University

  • Loren Pfeiffer

    Electrical Engineering, princeton university, Department of Electrical Engineering, Princeton University, Princeton University, Princeton Univ, Electrical Engineering, Princeton Univ, EE, Princeton University

  • Mansour Shayegan

    Princeton Univ, Electrical Engineering, Princeton Univ, Department of Electrical Engineering, Princeton University, EE, Princeton University