Measurement of recombination and single-vortex trapping of quasiparticles in a superconducting qubit

ORAL

Abstract

We measure the dynamics of quasiparticle relaxation over multiple orders of magnitude in density in superconducting transmon qubits using a contactless injection technique by microwave pulses. We demonstrate the power-law decay characteristics for quasiparticle recombination and exponential decay for single quasiparticle loss due to trapping effects, and find both mechanisms play a significant role in quasiparticle relaxation depending on device geometry. We observe quantized changes in quasiparticle trapping rate due to individual vortices, and thus quantitatively measure the interaction between non-equilibrium quasiparticles and a single vortex in a superconducting aluminum film. These results are described in Ref. [1]. [1] C. Wang et al. arXiv:1406.7300 [quant-ph]

–

Authors

  • Chen Wang

    Yale University, Yale Univ

  • Y.Y. Gao

    Yale University, Yale Univ

  • I.M. Pop

    Department of Applied Physics, Yale University, Yale University, Yale Univ

  • U. Vool

    Department of Applied Physics, Yale University, Yale University, Yale Univ

  • C. Axline

    Yale University, Yale Univ, Department of Applied Physics, Yale University

  • T. Brecht

    Yale University, Yale Univ

  • Reinier W. Heeres

    Yale University, Yale Univ, Departments of Applied Physics and Physics, Yale University

  • L. Frunzio

    Yale University, Yale Univ, Departments of Applied Physics and Physics, Yale University, Department of Applied Physics, Yale University

  • Gianluigi Catelani

    Peter Grunberg Institut (PGI-2), Forschungszentrum Julich PGI-2

  • M.H. Devoret

    Yale University, Yale Univ, Department of Applied Physics, Yale University, Departments of Applied Physics and Physics, Yale University

  • Leonid I. Glazman

    Yale University, Yale Univ, Department of Physics, Yale University, Departments of Physics and Applied Physics, Yale University, New Haven, CT 06511, USA

  • Robert Schoelkopf

    Yale University, Yale Univ, Departments of Applied Physics and Physics, Yale University, Department of Applied Physics, Yale University