Entangled Schrodinger cats in circuit QED: Experimental Architecture

ORAL

Abstract

The development of quantum information technology relies on creating and controling entanglement over an increasingly large Hilbert space. Superconducting cavities offer high-dimensional spaces for quantum states in a low-loss and hardware-efficient fashion, making it an ideal memory of quantum information and an important element towards fault-tolerant quantum computation. In this talk we present a cQED architecture that allows quantum control over the coherent state basis of two superconducting cavities with millisecond coherence. In particular, we show deterministic entanglement of coherent-state microwave fields in two superconducting cavities of the form: $\frac{1}{\sqrt 2 }\left( {\left| \right.\left. {\beta_{a} } \right\rangle \left| \right.\left. {\beta_{a} } \right\rangle \pm \left| - \right.\left. {\beta_{a} } \right\rangle \left| - \right.\left. {\beta_{a} } \right\rangle } \right)$. We engineer the capability to measure the joint photon number parity to achieve complete state tomography of the two-cavity state. Following widespread efforts of realizing ``Schrodinger's cat''-like mesoscopic superposition in various physical systems, this experiment demonstrates mesoscopic entanglement between two ``Schrodinger's cats''.

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Authors

  • Chen Wang

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

  • Yvonne Y. Gao

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

  • P. Reinhold

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

  • R. Heeres

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

  • N. Ofek

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

  • Kevin Chou

    • Yale University

  • C. Axline

    • Yale University

  • L. Frunzio

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

  • M. H. Devoret

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

  • R. J. Schoekopf

    • Yale University
    • Department of Applied Physics, Yale University
    • Department of Applied Physics and Physics, Yale University
    • Department of Physics and Applied Physics, Yale University, New Haven, Connecticut
    • Departments of Applied Physics and Physics, Yale University, New Haven, Connecticut, USA.
    • Yale University, Department of Applied Physics
    • Yale University Department of Applied Physics