InSbAs two-dimensional electron gases as a platform for topological superconductivity

ORAL

Abstract

Majorana zero-modes (MZMs), building blocks of topologically protected qubits, can be realized in semiconductors with strong spin-orbit interaction coupled to a superconductor. Among the candidate systems, hybrid two-dimensional electron gases (2DEGs) are of particular interest due to their inherent design flexibility and scalability.
Here, we discuss results on a new hybrid 2D platform consisting of a ternary 2DEG (InSbAs) coupled to epitaxially grown Aluminum. We show that this ternary has a large Landé g-factor of ~50, along with exceptionally strong spin-orbit coupling, exceeding the value for both InSb and InAs. Furthermore, the strength of this spin-orbit interaction is tuneable by the As concentration, in good agreement with theoretical predictions. Through spectroscopic measurements we show that the induced superconducting gap in this hybrid system is hard with a value close to that of bare Aluminum. The pristine semiconductor-superconductor interface is further confirmed by the observation of highly transparent Josephson junctions that can be used to create phase-controllable MZMs in a SQUID geometry.
These results establish InSbAs/Al 2DEGs as a promising new material system to realize topological superconductivity.

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Presenters

  • Christian Moehle

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • Delft University of Technology

Authors

  • Christian Moehle

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • Delft University of Technology

  • Chung Ting Ke

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Candice Thomas

    • Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA
    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • CEA, LETI, MINATEC Campus, 38054 Grenoble, France
    • Department of Physics and Astronomy, Purdue University

  • Di Xiao

    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Department of Physics and Astronomy, Purdue University

  • Mario Lodari

    • Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Vincent van de Kerkhof

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • Delft University of Technology

  • Ruben Termaat

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • Delft University of Technology

  • Saurabh Karwal

    • QuTech and Netherlands Organization for Applied Scientific Research (TNO)
    • Netherlands Organization for Applied Scientific Research

  • Sara Metti

    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Department of Physics and Astronomy, Purdue University

  • Charles Guinn

    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Department of Physics and Astronomy, Purdue University

  • Raymond Kallaher

    • Microsoft Quantum at Station Q Purdue, Purdue University
    • Microsoft Quantum at station Q Purdue
    • Microsoft Station Q Purdue, Purdue University

  • Geoffrey C. Gardner

    • Purdue University
    • Purdue Univ
    • Microsoft Quantum at Station Q Purdue, Purdue University
    • Purdue University, Microsoft Station Q, West Lafayette, Indiana 47907, USA
    • Microsoft Quantum at station Q Purdue
    • Microsoft Station Q Purdue, Purdue University
    • Birck Nanotechnology Center and Microsoft Quantum Purdue, Purdue University

  • Giordano Scappucci

    • Delft University of Technology
    • QuTech, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, TU Delft
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Michael Manfra

    • Purdue University
    • Purdue Univ
    • Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA
    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Niels Bohr Institute, Microsoft Station Q, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
    • Department of Physics and Astronomy, Purdue University
    • Birck Nanotechnology Center and Microsoft Quantum Purdue, Purdue University

  • Srijit Goswami

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, 2600 GA Delft, The Netherlands
    • Delft University of Technology