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Spin-split Andreev levels in a quantum dot with superconducting leads: microwave spectroscopy

ORAL

Abstract

We use a hybrid superconductor-semiconductor transmon device to perform spectroscopy of a quantum dot Josephson junction tuned to be in a spin-1/2 ground state with an unpaired quasiparticle. Due to spin-orbit coupling, we resolve two flux-sensitive branches in the transmon spectrum, depending on the spin of the quasi-particle. A finite magnetic field shifts the two branches in energy, favoring one spin state and resulting in the anomalous Josephson effect. We demonstrate the excitation of the direct spin-flip transition using all-electrical control. Manipulation and control of the spin-flip transition allow for the implementation of charging energy protected Andreev spin qubits.

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Publication: Spectroscopy of spin-split Andreev levels in a quantum dot with superconducting leads at preprint server arXiv under https://arxiv.org/abs/2208.09314

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

    TU Delft, Delft University of Technology, Qutech, Delft University of Technology

  • Rok Zitko

    Jozef Stefan Institute, University of Ljubljana

  • Lukas Johannes Splitthoff

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

  • Lukas Grunhaupt

    Delft University of Technology

  • Jaap J Wesdorp

    Delft University of Technology, Qutech, Delft University of Technology

  • Yu Liu

    University of Copenhagen, Niels Bohr Institute, University of Copenhagen

  • Leo P Kouwenhoven

    Delft University of Technology, Qutech, Delft University of Technology

  • Ramon Aguado

    CSIC - Madrid

  • Christian K Andersen

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

  • Angela Kou

    University of Illinois at Urbana-Champaign

  • Bernard Van Heck

    Leiden University