Multiplexed photon number measurement of a cavity using the fluorescence of a coupled qubit.

ORAL

Abstract

Measuring the photon number of an electromagnetic mode in a quantum nondemolition manner is instrumental to control the quantum state of a cavity, detect photon emission or measure work. In the microwave domain it can be done using the dispersive coupling between the cavity of interest and a coupled Rydberg atom or superconducting circuit. This method has been used successfully to count up to about a dozen photons, to realize Quantum Zeno dynamics experiments, or count photon number parity. Yet this technique has constraints on the measurement time. In particular it increases with the maximal number of photons. In this contribution, we present a technique that avoids this constraint by using the resonant fluorescence of a qubit coupled to the resonator of interest and a multiplexing measurement of the fluorescence field. We show an experiment where an independent quantum state tomography can be performed on the resonator to compare the result of the conventional method to this new technique.

*We thank MIT Lincoln labs that provided us a Traveling Wave Amplifier. The project was supported by the foundation Simone et Cino Del Duca.

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Presenters

  • Antoine Essig

    • Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France

Authors

  • Antoine Essig

    • Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France

  • Quentin Ficheux

    • University of Maryland, College Park
    • Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France

  • Peronnin Theau

    • Université Lyon, ENS de Lyon, Université Claude Bernard, CNRS, Laboratoire de Physique,F-69342 Lyon, France

  • Nathanael Pierre Cottet

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

  • Raphael Lescanne

    • Laboratoire Pierre Aigrain, Département de physique de l'ENS, Ecole normale supérieure,PSL Research University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Univer

  • Alain Sarlette

    • Centre Automatique et Systèmes, Mines ParisTech, PSL Research University,60 Boulevard Saint-Michel, 75272 Paris Cedex 6, France

  • Pierre Rouchon

    • Centre Automatique et Systèmes, Mines ParisTech, PSL Research University,60 Boulevard Saint-Michel, 75272 Paris Cedex 6, France

  • Zaki Leghtas

    • Laboratoire Pierre Aigrain, Département de physique de l'ENS, Ecole normale supérieure,PSL Research University, Université Paris Diderot, Sorbonne Paris Cité, Sorbonne Univer

  • Benjamin Huard

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