Magnetic circular x-ray-dichroism study of Co/Pt(111)

Abstract

Magnetic circular x-ray-dichroism measurements at the Co ${L}_{2,3}$ edges of the Co/Pt(111) interface are presented. Ultrathin Co films, deposited and measured at room temperature, order magnetically above a thickness of 1.8 monolayers and show magnetic anisotropy perpendicular to the surface up to coverage of at least 5 monolayers. An enhancement of the orbital magnetic momentum relative to the bulk value of Co metal is observed. A further increase after addition of a thick Pt overlayer reveals the influence of hybridization at the Co/Pt interface. Observations of magnetic surface alloys with perpendicular anisotropy are also reported.