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.

*Research supported by funding from the Dutch Research Council (NWO), the allowance for Top consortia for Knowledge and Innovation (TKI's) from the Dutch Ministry of Economic Affairs and the Microsoft Quantum initiative.

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