Measurement of quantum jumps of a fluxonium qubit using a Dimer Josephson Junction Array Amplifier operated at high power

ORAL

Abstract

Josephson parametric amplifiers have become an essential element in cQED dispersive readout measurement schemes, enabling single-shot qubit readout. Over the last decade there was significant progress in the increase of their saturation power [1,2,3,4], which now reaches several thousand photons per μs.
We demonstrate high saturation power in a Dimer Josephson Junction Array Amplifier [4] operating with a quantum efficiency of 60%. We use this parametric amplifier to perform dispersive readout of a fluxonium qubit with a superinductor made of granular aluminum [5]. We present quantum jump measurements acquired using up-to 100 circulating photons in the readout resonator, which allowed qubit state discrimination in tens of nanoseconds.

[1] C. Eichler and A. Wallraff, EPJ Quantum Technologies 1, 2 (2014)
[2] L. Planat et.al., PRA 11, 034014 (2019)
[3] V. V. Sivak et.al., arxiv:1909.08005
[4] P. Winkel & I. Takmakov et.al., arxiv:1909.08037
[5] L. Grünhaupt & M. Spiecker, et al. Nature Materials 18, 816–819 (2019)

Presenters

  • Ivan Takmakov

    • Karlsruhe Institute of Technology

Authors

  • Ivan Takmakov

    • Karlsruhe Institute of Technology
  • Patrick Winkel

    • Karlsruhe Institute of Technology
  • Farshad Foroughi

    • Neel Institute, University Grenoble Alpes, CNRS
    • NEEL
    • Institut Neel
    • Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
    • Univ. Grenoble Alpes and Institut Néel, CNRS, 38000 Grenoble, France
  • Martin Spiecker

    • Karlsruhe Institute of Technology
  • Lukas Gruenhaupt

    • Physikalisches Institut, Karlsruhe Institute of Technology
    • Karlsruhe Institute of Technology
  • Daria Gusenkova

    • Karlsruhe Institute of Technology
  • Luca Planat

    • Neel Institute, University Grenoble Alpes, CNRS
    • NEEL
    • Institut Neel
    • Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
    • Univ. Grenoble Alpes and Institut Néel, CNRS, 38000 Grenoble, France
  • Dennis Rieger

    • Karlsruhe Institute of Technology
  • Alexey V. Ustinov

    • Karlsruhe Institute of Technology
  • Wolfgang Wernsdorfer

    • Karlsruhe Institute of Technology
  • Ioan-Mihai Pop

    • Physikalisches Institut, Karlsruhe Institute of Technology
    • Karlsruhe Institute of Technology
  • Nicolas Roch

    • Neel Institute, University Grenoble Alpes, CNRS
    • NEEL
    • Institut Neel
    • Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
    • Univ. Grenoble Alpes and Institut Néel, CNRS, 38000 Grenoble, France
    • Université Grenoble Alpes, CNRS, Institut NEEL UPR2940, Grenoble, France