Effect of Material Quality on Superconducting Proximity Effect in Al-InAs Heterostructures

ORAL

Abstract

Renewed theoretical and experimental interest in InAs heterostructure with two-dimensional electron systems (2DESs) confined to the surface is partly due to their potential applications in topological and superconducting quantum computation. Here we study Josephson junctions with epitaxial Al-InAs contacts and find large super currents and substantial product of ICRN in our high mobility wafers. We also compare the product of excess current and normal resistance, IexeRN of high mobility samples and low mobility samples. The excess current is negligible in the devices made of lower mobility Al-InAs samples whereas it is substantial and independent of gate voltages and junction length in high mobility sample. For the devices made with high mobility samples, we found that ICRN/Δ~2.2. Further we discuss how the above parameters are linked to the material quality of the samples.

*We acknowledge the support of US Army Office of Research and DARPA.

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Presenters

  • Kaushini Wickramasinghe

    • University of Oklahoma
    • Department of Physics, New York University
    • Physics, New York University
    • Physics, University of Maryland, College Park
    • Center for Quantum Phenomena, Department of Physics, New York University
    • University of Maryland, College Park

Authors

  • Kaushini Wickramasinghe

    • University of Oklahoma
    • Department of Physics, New York University
    • Physics, New York University
    • Physics, University of Maryland, College Park
    • Center for Quantum Phenomena, Department of Physics, New York University
    • University of Maryland, College Park

  • William Andrew Mayer

    • Department of Physics, New York University
    • Physics, New York University
    • Center for Quantum Phenomena, Department of Physics, New York University

  • Joseph Yuan

    • Department of Physics, New York University
    • Physics, New York University
    • Center for Quantum Phenomena, Department of Physics, New York University

  • Tri Nguyen

    • Physics, City University of New York

  • Matthieu Dartiailh

    • Physics, New York University
    • Center for Quantum Phenomena, Department of Physics, New York University
    • Laboratoire Pierre Aigrain UMR 8551, Ecole normale Supérieure - PSL Research university, CNRS, Université Pierre et Marie Curie - Sorbonne Universités, Université Paris Dider

  • Kasra Sardashti

    • Department of Science and Math, Fashion Institute of Technology

  • Vladimir Manucharyan

    • Department of Physics, University of Maryland
    • University of Maryland, College Park
    • University of Maryland-College Park
    • Physics, University of Maryland, College Park
    • Department of Physics, University of Maryland, College Park, MD 20742
    • University of Maryland - College Park

  • Javad Shabani

    • Department of Physics, New York University
    • Physics, New York University
    • Center for Quantum Phenomena, Department of Physics, New York University
    • Center for Quantum Phenomena, New York University
    • New York University
    • Physics, Harvard University