Investigating the mechanism of single-electron tunneling in charge-parity-sensitive transmons

ORAL

Abstract

Single-electron tunneling across Josephson junctions in superconducting qubits contributes to decoherence and limits qubit performance. In the past, such decoherence was exclusively attributed to pre-existing non-equilibrium quasiparticles that tunnel across junctions and exchange energy with the qubit. However, it was recently predicted that high-frequency photons can be efficiently absorbed in transmon Josephson junctions and induce single-electron tunneling. This process requires no pre-existing quasiparticles; in fact it generates two quasiparticles and, in doing so, can change the qubit state. Past measurements of single-electron tunneling-induced excitation and relaxation in charge-parity-sensitive transmons were consistent with photon-assisted tunneling. Here, we will present theoretical and experimental results demonstrating that adding flux-tunability to a charge-parity-sensitive transmon can distinguish the contributions of different single-electron tunneling processes in our devices.

*Work supported by Army Research Office and Air Force Office of Scientific Research

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Presenters

  • Spencer Diamond

    • TU Delft
    • Yale University
    • Departments of Applied Physics and Physics, Yale University

Authors

  • Spencer Diamond

    • TU Delft
    • Yale University
    • Departments of Applied Physics and Physics, Yale University

  • Valla Fatemi

    • Yale University
    • Departments of Applied Physics and Physics, Yale University

  • Max Hays

    • Yale University
    • Departments of Applied Physics and Physics, Yale University

  • Kyle Serniak

    • MIT Lincoln Lab
    • MIT Lincoln Laboratory
    • MIT-Lincoln Lab
    • Lincoln Laboratory, MIT
    • MIT - Lincoln Laboratory

  • Luigi Frunzio

    • Applied Physics Department, Yale University
    • Yale University
    • Applied Physics, Yale University
    • Department of Applied Physics and Physics, Yale University

  • Robert J Schoelkopf

    • Yale University
    • Applied Physics, Yale University
    • Department of Applied Physics and Physics, Yale University

  • Leonid Glazman

    • Yale University
    • Departments of Applied Physics and Physics, Yale University

  • Michel Devoret

    • Yale University
    • Applied Physics Department, Yale University
    • Yale
    • Department of Applied Physics and Physics, Yale University
    • Applied Physics, Yale University
    • Departments of Applied Physics and Physics, Yale University