Yu-Shiba-Rusinov bands in superconductors in contact with a magnetic insulator

Highlights: • Superconductor-Ferromagnet (SF) heterostructures are of interest due to the spin-dependent interaction of Cooper pairs with the magnetization. • We address the effect of a magnetic insulator on the density of states of a superconductor based on a recently developed boundary condition for strongly spin-dependent interfaces. • We show that the boundary to a magnetic insulator has a similar effect like the presence of magnetic impurities and can lead to the formation of Shiba bands. • We study the interaction of two Shiba bands and show that their hybridization depends on the details of the spin-dependent scattering parameters. Superconductor-Ferromagnet (SF) heterostructures are of interest due to numerous phenomena related to the spin-dependent interaction of Cooper pairs with the magnetization. Here we address the effects of a magnetic insulator on the density of states of a superconductor based on a recently developed boundary condition for strongly spin-dependent interfaces. We show that the boundary to a magnetic insulator has a similar effect like the presence of magnetic impurities. In particular we find that the impurity effects of strongly scattering localized spins leading to the formation of Shiba bands can be mapped onto the boundary problem.