Kaveh Delfanazari

Quasiparticle Dynamics in NbN Superconducting Microwave Resonators at Single Photon Regime

  1. Paniz Foshat,
  2. Shima Poorgholam-khanjari,
  3. Valentino Seferai,
  4. Hua Feng,
  5. Susan Johny,
  6. Oleg A. Mukhanov,
  7. Matthew Hutchings,
  8. Robert H. Hadfield,
  9. Martin Weides,
  10. and Kaveh Delfanazari
Exchanging energy below the superconducting gap introduces quasiparticle energy distributions in superconducting quantum circuits, which will be responsible for their decoherence. This
study examines the impact of quasiparticle energy on the performance of NbN superconducting microwave coplanar waveguide resonators on silicon chips. We measured the resonance frequency and internal quality factor in response to temperature sweeps to evaluate the effect of quasiparticle dynamics. Moreover, by calculating the complex conductivity of the NbN film, we identified the contribution of quasiparticle density to the experimental results.
arxiv pdf