Effects of Nonmagnetic Impurities and Subgap States on the Kinetic Inductance, Complex Conductivity, Quality Factor, and Depairing Current Density

  title={Effects of Nonmagnetic Impurities and Subgap States on the Kinetic Inductance, Complex Conductivity, Quality Factor, and Depairing Current Density},
  author={Takayuki Kubo},
  journal={Physical Review Applied},
  • T. Kubo
  • Published 1 October 2021
  • Physics
  • Physical Review Applied
We investigate how a combination of a nonmagnetic-impurity scattering rate γ and finite subgap states parametrized by Dynes Γ affects various physical quantities relevant to to superconducting devices: kinetic inductance Lk, complex conductivity σ, surface resistance Rs, quality factor Q, and depairing current density Jd. All the calculations are based on the Eilenberger formalism of the BCS theory. We assume the device materials are extreme type-II s-wave superconductors. It is well known that… 


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