One dimensional edge localized YSR states in CrCl on NbSe.

Magnet/superconductor hybrid systems have been put forward as a platform for realizing topological superconductivity. We investigated the heterostructure of ferromagnetic monolayer CrCl and superconducting NbSe. Using low-temperature scanning tunneling microscopy, we observe topologically trivial Yu-Shiba-Rusinov (YSR) states localized at the edge of CrCl islands. DFT simulations reveal that the Cr atoms at the edge have an enhanced -orbital DOS close to . This leads to an exchange coupling between these atoms and the substrate that rationalizes the edge-localization of the YSR states.