Driven dynamics of a qubit tunably coupled to a harmonic oscillator

ORAL

Abstract

We have investigated the driven dynamics of a superconducting flux qubit that is tunably coupled to a microwave resonator. We find that the qubit experiences an additional oscillating field mediated by off-resonant driving of the resonator, leading to unanticipated, strong modifications of the qubit Rabi frequency. Low-frequency noise in the coupling parameter translates to an effective noise in the amplitude of the drive field, causing a reduction of the coherence time during driven evolution. The noise can be mitigated with the rotary-echo pulse sequence, which, for driven systems, is analogous to the Hahn-echo sequence.

*This work is sponsored by the Department of the Air Force under contract number FA8721-05-C-0002. Opinions, interpretations, conclusions, and recommendations are those of the author(s) and are not necessarily endorsed by the United States government.

Authors

  • Simon Gustavsson

    • Massachusetts Institute of Technology
  • Jonas Bylander

    • Massachusetts Institute of Technology
  • Fei Yan

    • Massachusetts Institute of Technology
  • Pol Forn-Diaz

    • Massachusetts Institute of Technology
  • Vlad Bolkhovsky

    • MIT Lincoln Lab
  • Danielle Braje

    • MIT Lincoln Lab
  • Steven Spector

    • MIT Lincoln Lab
  • Ben Turek

    • MIT Lincoln Lab
  • Paul B. Welander

    • MIT Lincoln Lab
  • Fumiki Yoshihara

    • NEC
  • David. G. Cory

    • University of Waterloo
  • Yasunobu Nakamura

    • NEC
  • William D. Oliver

    • Massachusetts Institute of Technology, MIT Lincoln Lab