Quantum Magnetism and Topological Superconductivity in Yu-Shiba-Rusinov Chains.

  title={Quantum Magnetism and Topological Superconductivity in Yu-Shiba-Rusinov Chains.},
  author={Jacob F. Steiner and Christophe Mora and Katharina J. Franke and Felix von Oppen},
  journal={Physical review letters},
  volume={128 3},
Chains of magnetic adatoms on superconductors have been discussed as promising systems for realizing Majorana end states. Here, we show that dilute Yu-Shiba-Rusinov (YSR) chains are also a versatile platform for quantum magnetism and correlated electron dynamics, with widely adjustable spin values and couplings. Focusing on subgap excitations, we derive an extended t-J model for dilute quantum YSR chains and use it to study the phase diagram as well as tunneling spectra. We explore the… 

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