Microwave resonant activation in hybrid single-gap/two-gap Josephson tunnel junctions

ORAL

Abstract

Microwave resonant activation is a powerful technique to study classical and quantum systems, experimentally realized in Josephson junctions. We have recently reported the first demonstration of resonant activation experiments on hybrid, thin film Josephson heterojunctions consisting of a multi-gap superconductor (MgB2) separated from a single-gap superconductor (Pb or Sn) by an insulating barrier [1]. In this presentation, we expound on several quantum signatures exhibited in superconducting-to-normal state switching in these devices, including a leveling off of the Tesc vs. T curve and Lorentzian peaks in the escape rate enhancement. We also discuss features which are commonly ascribed to multi-photon transitions between quantum levels inside a junction, and the implications of these. References: 1. S.Carabello, et. al., J. Appl. Phys. 120, 123904 (2016)

*R.C.R. acknowledges partial support from National Science Foundation Grant DMR-1555775.

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Authors

  • Roberto Ramos

    • University of the Sciences

  • Steven Carabello

    • Drexel University

  • Joseph Lambert

    • Drexel University
    • University of the Sciences

  • Jerome Mlack

    • Drexel University

  • Wenqing Dai

    • Pennsylvania State University

  • Qi Li

    • Pennsylvania State University
    • Penn State University

  • Ke Chen

    • Temple University

  • Daniel Cunnane

    • Temple University

  • Xiaoxing Xi

    • Temple University
    • Temple University, Department of Physics, Philadelphia PA 19122
    • Physics Department, Temple University, Philadelphia PA 19122, USA
    • Department of Physics, Temple University, Philadelphia, PA, USA
    • Temple Univ