Cavity-photon induced state transitions in a coupled Fluxonium qubit system

ORAL

Abstract

Superconducting qubits are a subject of intense research as a platform for scalable quantum computing. While transmon qubits have received a lot of attention, the less ubiquitous Fluxonium qubit has been shown to have long life-times and gates unlimited by level anharmonicity [1]. Despite this, little research has been put into studying multi-Fluxonium devices. Here, one of the difficulties is understanding how their rich level structure can make them prone to measurement photons inducing transitions out of the qubit subspace [2]. We present a systematic study of a system comprising two capacitively coupled Fluxonium qubits sharing the same read-out cavity. By tracking the state dependent transmission of the read-out pulse, we determine the transition rates from state i to state j of the coupled system using a forward-backward analysis [3] to characterize these cavity induced transitions. By varying the flux bias of the system and the population of the cavity, we characterize the fidelity of this read-out.

[1] L.B. Nguyen et al., Phys. Rev. X 9 041041, 2019
[2] D. Sank et al., Phys. Rev. Lett. 117 190503, 2016
[3] T. Rybarczyk et al., Physical Review A 91 062116, 2015

Presenters

  • Jeremy Stevens

    • ENS de Lyon
    • Ecole Normale Superieure de Lyon

Authors

  • Jeremy Stevens

    • ENS de Lyon
    • Ecole Normale Superieure de Lyon
  • Alexis Jouan

    • ENS de Lyon
  • Nathanael Cottet

    • Yale University
    • Physics, Yale University
    • Ecole Normale Superieure de Lyon
  • Long B Nguyen

    • University of Maryland, College Park
    • Physics, University of California, Berkeley
    • University of Maryland
  • Aaron Somoroff

    • University of Maryland, College Park
    • University of Maryland
  • Quentin Ficheux

    • University of Maryland, College Park
    • University of Maryland
    • Ecole Normale Superieure de Lyon
    • Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon,France
  • Audrey Bienfait

    • University of Chicago
    • Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France
    • ENS de Lyon
    • Ecole Normale Superieure de Lyon
    • Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France
    • Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon,France
  • Vladimir Manucharyan

    • University of Maryland, College Park
    • Department of Physics, University of Maryland
    • University of Maryland
  • Benjamin Huard

    • Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France
    • ENS de Lyon
    • ENS Lyon
    • Ecole Normale Superieure de Lyon
    • Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France
    • Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon,France