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Singlet-doublet transitions of a quantum dot Josephson junction revealed in a transmon circuit: finite temperature transitions

ORAL

Abstract

Probing the mesoscopic physics of hybrid superconductor-semiconductor elements using a circuit quantum electrodynamics (cQED) architecture offers enhanced energy and time resolution compared to DC transport techniques, and allows for additional methods of coherent control. Here we investigate the parity phase diagram of a quantum dot with superconducting leads using a hybrid transmon architecture. Our device is composed of a transmon where the Josephson coupling is determined by a gate-controlled quantum dot defined in an InAs-Al nanowire.

In addition to mapping out the zero-temperature parity phase diagram, we measure the finite-temperature quasiparticle dynamics across the ground state transitions. We find that the charging energy of the quantum dot can extend the fermion parity lifetime of the junction up to milliseconds.

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Presenters

  • Arno Bargerbos

    Delft University of Technology, Qutech, Delft University of Technology

Authors

  • Arno Bargerbos

    Delft University of Technology, Qutech, Delft University of Technology

  • Marta Pita Vidal

    Delft University of Technology

  • Rok Zitko

    University of Ljubljana, Jozef Stefan Institute

  • Jesus Avila

    CSIC - Madrid, CSIC

  • Lukas Johannes Splitthoff

    Delft University of Technology, Qutech, Delft University of Technology

  • Lukas Grunhaupt

    Delft University of Technology

  • Jaap J Wesdorp

    Delft University of Technology, Qutech, Delft University of Technology

  • Christian Kraglund K Andersen

    Delft University of Technology, Delft University of technology

  • Yu Liu

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

  • Peter Krogstrup

    Microsoft Quantum Materials Lab Copenhagen, University of Copenhagen and Microsoft Quantum Materials Lab Copenhagen, ekrogst@microsoft.com, Quantum Materials Lab Copenhagen, Microsoft, Microsoft Quantum Materials Lab, Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen

  • Ramon Aguado

    CSIC - Madrid

  • Angela Kou

    University of Illinois at Urbana-Champaign

  • Bernard van Heck

    Leiden University, Microsoft Corp, Microsoft Quantum lab Delft, University of Leiden