Impurity-induced subgap states in superconductors with inhomogeneous pairing

  title={Impurity-induced subgap states in superconductors with inhomogeneous pairing},
  author={Anton Bespalov},
  journal={Physical Review B},
  • A. Bespalov
  • Published 4 September 2019
  • Physics
  • Physical Review B
We study subgap states induced by a single impurity in an s-wave superconductor with suppressed pairing. For concreteness, we consider a bulk superconductor containing a normal spherical region. We find that a point impurity in this system induces two Yu-Shiba-Rusinov states inside the minigap instead of one, which one would have in a homogeneous superconductor. Moreover, the subgap states appear even if the impurity is nonmagnetic. We prove that this result actually holds almost for any… 

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