Physical Review B
Chains of magnetic atoms placed on the surface of an s-wave superconductor with large spin-orbit coupling provide a promising platform for the realization of topological superconducting states characterized by the presence of Majorana zero-energy modes. In this work, we study the properties of one-dimensional chains of Yu-Shiba-Rusinov states induced by magnetic impurities using a realistic model for the magnetic atoms that includes the presence of multiple scattering channels. These channels are mixed by spin-orbit coupling and, via the hybridization of the Yu-Shiba-Rusinov states at different sites of the chain, result in a multiband structure for the chain. We obtain the topological phase diagram for such a band structure and show that the inclusion of higher bands can greatly enlarge the phase space for the realization of topological states.
Zhang, J., Kim, Y., Rossi, E., & Lutchyn, R. M. (2016). Topological superconductivity in a multichannel Yu-Shiba-Rusinov chain. Physical Review B, 93(2), 024507.