Gradiometric persistent current flux qubit with tunable tunnel coupling

ORAL

Abstract

The persistent current flux qubit is a Josephson junction based superconducting circuit exhibiting a strong anharmonicity in combination with excellent coherence times of more than 10\,$\mu$s. However, quantum coherence decreases drastically away from an optimal point and a controlled design of the transition frequency at this point is demanding with respect to fabrication stability. Here, we present the spectroscopic analysis of a gradiometric flux qubit, where the tunnel coupling can be tuned from a few hundreds of Megahertz to several Gigahertz.

*Supported by the DFG via SFB 631 and by the German Excellence Initiative via NIM.

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Authors

  • F. Deppe

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • M. Schwarz

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • J. Goetz

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • A. Baust

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • M. Haeberlein

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • E. Hoffmann

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • E.P. Menzel

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • F. Wulschner

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • L. Zhong

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • A. Marx

    • Walther-Meissner-Institute and TU Munich, Garching, Germany

  • R. Gross

    • Walther-Meissner-Institute and TU Munich, Garching, Germany