Spin orientation transition across the graphene/nickel thin film interface

Matsumoto, Yoshihiro; Entani, Shiro; Koide, Akihiro*; Otomo, Manabu; Avramov, P.; Naramoto, Hiroshi*; Amemiya, Kenta*; Fujikawa, Takashi*; Sakai, Seiji

The spin-polarized electronic structures across the interface between single-layer graphene and a Ni(111) thin film are explored by employing the depth-resolved X-ray absorption and magnetic circular dichroism spectroscopy with the atomic layer resolution. The depth-resolved Ni L-edge analysis clarifies that the Ni atomic layers adjacent to the interface show a transition of the spin orientation to the perpendicular one in contrast with the in-plane one in the bulk region. The C K-edge analysis reveals the intensifying of the spin-orbital interactions induced by the -d hybridization at the interface as well as out-of-plane spin polarization at the band region of graphene. The present study indicates the importance of the interface design at the atomic layer level for graphene-based spintronics.