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Yu-Shiba-Rusinov states in Ising superconductors

Michael Hein1, Juan Carlos Cuevas2, and Wolfgang Belzig1

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Phys. Rev. B 114, 094502 – Published 5 August, 2026

DOI: https://doi.org/10.1103/w7dl-pxfk

Abstract

The nature of the superconducting state in two-dimensional transition-metal dichalcogenides remains under active debate. A widely used description invokes so-called Ising superconductivity. In this work, we investigate theoretically this pairing state by employing single magnetic impurities as local probes of the superconducting condensate. We analyze the formation of Yu-Shiba-Rusinov bound states in the presence of Ising spin-orbit coupling and an in-plane magnetic field to study how their spectral properties encode the underlying pairing structure. We identify distinct features in the bound-state spectrum and tunneling response that differentiate this system from conventional superconductors. Our results demonstrate that magnetic impurities provide a sensitive probe of the structure of the superconducting state and yield experimentally accessible signatures of unconventional aspects of Ising superconductivity.

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Outline

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Phys. Rev. B 114, 094502– Published 5 August, 2026
  • Received 12 May 2026
  • Revised 16 July 2026
  • Accepted 17 July 2026
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