Controlling the charge dispersion of a nearly-open superconducting island

ORAL

Abstract

We investigate the charge dispersion of a nanowire transmon hosting an accidental resonant level in the junction. We observe rapid suppression of the charge dispersion consistent with the scaling law resulting from diabatic transitions between Andreev bound states. We also observe improved qubit coherence times at the point of highest charge dispersion suppression. Our observations further our fundamental understanding of charging effects in superconductors and suggests novel approaches for building charge-insensitive qubits. Finally, we will discuss prospects for exploring the competition between superconductivity and Coulomb blockade by embedding a gate-defined quantum dot in the junction of the nanowire transmon.

*This work has been supported by funding from the Dutch Research Council (NWO) and the Microsoft Quantum initiative.

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Presenters

  • Arno Bargerbos

    • Delft University of Technology
    • QuTech, Delft University of Technology
    • Qutech, Delft University of Technology

Authors

  • Arno Bargerbos

    • Delft University of Technology
    • QuTech, Delft University of Technology
    • Qutech, Delft University of Technology

  • Willemijn Uilhoorn

    • Delft University of Technology

  • Marta Pita Vidal

    • Delft University of Technology

  • Chung-Kai Yang

    • Quantum Lab Delft, Microsoft

  • Peter Krogstrup

    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen
    • Microsoft Quantum Materials Lab and Center for Quantum Devices, Niels Bohr Institute,8University of Copenhagen, Kanalvej 7, 2800 Kongens Lyngby, Denmark
    • Niels Bohr Institute, University of Copenhagen
    • Quantum Materials Lab Copenhagen, Microsoft
    • University of Copenhagen
    • Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
    • Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen
    • Microsoft Quantum Materials Lab, University of Copenhagen
    • Niels Bohr Institute, Copenhagen
    • Niels Bohr Institute

  • Leo Kouwenhoven

    • Microsoft station Q Delft
    • Microsoft Station Q Delft
    • Quantum Lab Delft, Microsoft
    • Microsoft Quantum Lab Delft
    • Quantum lab Delft, Microsoft
    • Microsoft Corp
    • Station Q Delft, Microsoft

  • Gijs De Lange

    • Quantum Lab Delft, Microsoft
    • Quantum lab Delft, Microsoft
    • Microsoft Corp

  • Bernard Van Heck

    • Quantum Lab Delft, Microsoft
    • Microsoft
    • Quantum lab Delft, Microsoft
    • Microsoft Quantum Lab Delft, Delft University of Technology, 2600 GA Delft, The Netherlands

  • Angela Kou

    • Illinois Quantum Information Science and Technology Center, University of Illinois at Urbana-Champaign
    • University of Illinois at Urbana-Champaign