Phase control of zero energy modes in topological Josephson junctions

ORAL

Abstract

Recent works have realized Majorana zero modes in planar Josephson junctions consisting of a semiconductor with strong spin-orbit coupling proximitized by two superconducting leads. Such systems offer the tantalizing possibility of using the phase difference Φ across the two superconductors as a new experimental knob to tune into and out of the topological regime, possibly at ultra-fast timescales, apart from having advantages such as reduced sensitivity to chemical potential tuning and appearance of Majorana bound states at zero magnetic field. Here, we demonstrate strong phase control of Andreev bound states that emerge from the gap at Φ~0 and coalesce at zero energy at Φ~π. The zero energy modes at Φ~π appear at in-plane magnetic fields as low as ~220 mT and persist robustly with variations of in-plane Zeeman field and gate voltages in a wide range. At larger in-plane magnetic fields, the zero energy modes become phase independent and stick for all values of Φ. We also study the behavior of the zero energy states with respect to large out-of-plane magnetic fields that can tune the phase texture within the Josephson junction, and possibly result in motion of Majorana zero modes.

*This work was supported by the Danish National Research Foundation and Microsoft.

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Presenters

  • Abhishek Banerjee

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Center for Quantum Devices and Microsoft Quantum Lab - Copenhagen, University of Copenhagen
    • Center for Quantum Devices, Microsoft Quantum Lab – Copenhagen and Niels Bohr Institute, University of Copenhagen

Authors

  • Abhishek Banerjee

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Center for Quantum Devices and Microsoft Quantum Lab - Copenhagen, University of Copenhagen
    • Center for Quantum Devices, Microsoft Quantum Lab – Copenhagen and Niels Bohr Institute, University of Copenhagen

  • Md. Ahnaf Rahman

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen

  • Antonio Fornieri

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Center for Quantum Devices and Microsoft Quantum Lab - Copenhagen, University of Copenhagen
    • Center for Quantum Devices, Microsoft Quantum Lab – Copenhagen and Niels Bohr Institute, University of Copenhagen

  • Alexander Whiticar

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Center for Quantum Devices and Microsoft Quantum Lab - Copenhagen, University of Copenhagen
    • Center for Quantum Devices, Microsoft Quantum Lab – Copenhagen and Niels Bohr Institute, University of Copenhagen

  • Asbjorn Drachmann

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Center for Quantum Devices, Microsoft Quantum Lab – Copenhagen and Niels Bohr Institute, University of Copenhagen

  • Tyler Lindeman

    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University
    • Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA
    • Department of Physics and Astronomy, PURDUE UNIVERSITY

  • Sergei Gronin

    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University
    • Microsoft Quantum at Station Q Purdue
    • Birck Nanotechnology Center and Microsoft Quantum Purdue, Purdue University
    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA
    • Microsoft Quantum Purdue

  • Candice Thomas

    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University
    • Microsoft Quantum at Station Q Purdue
    • Department of Physics and Astronomy and Birck Nanotechnology Center, Purdue University
    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Purdue University
    • Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA

  • Geoffrey C. Gardner

    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, Purdue University
    • Microsoft Quantum at Station Q Purdue
    • Materials Engineering, Purdue University
    • Purdue University
    • Microsoft Quantum at Station Q Purdue, Purdue University

  • Michael Manfra

    • Physics and Astronomy, Purdue Univ
    • Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, School of Materials Engineering, School of Electrical and Computer Engineering, Purdue
    • Purdue Univ
    • Purdue University
    • Microsoft Quantum at Station Q Purdue
    • Department of Physics and Astronomy, Birck Nanotechnology Center, Microsoft Quantum Purdue, School og Materials Engineering & School of Electrical and Computer Engineering, P
    • Physics and Astronomy, Purdue University
    • Department of Physics and Astronomy and Station Q Purdue, Purdue University
    • Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA
    • Department of Physics and Astronomy, PURDUE UNIVERSITY
    • Department of Physics and Astronomy, Microsoft Quantum Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
    • Physics, Purdue University

  • Charles Marcus

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Microsoft Quantum Lab Copenhagen and Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
    • Univ of Copenhagen
    • Center for Quantum Devices and Microsoft Quantum Lab - Copenhagen, University of Copenhagen
    • Center for Quantum Devices, Microsoft Quantum Lab – Copenhagen and Niels Bohr Institute, University of Copenhagen
    • Microsoft Corp
    • Niels Bohr Institute, University of Copenhagen