Crystallographic origin of perpendicular magnetic anisotropy in CoPt film: polarized x-ray absorption study

Crystallographic structure, growth induced miscibility gap and strain in Ta/Co 100− x Pt x (0 ⩽ x ⩽ 43 at%)/Ru/Ta/glass films deposited at ambient temperature were investigated using polarized x-ray absorption spectroscopy to clarify the origin of observed perpendicular magnetic anisotropy (PMA) in Co 72 Pt 28 film. Extended x-ray absorption fine structure spectroscopy data at Co K -edge showed that Co has a similar local atomic environment and averaged interatomic distance in the in-plane and out-of-plane polarization geometries for Co 72 Pt 28 , ruling out the contribution of magneto-elastic anisotropy and growth induced structural anisotropy as the origin of PMA. A large PMA in Co 72 Pt 28 film was attributed to the preferred hexagonal close-packed stacking as observed using the x-ray absorption near-edge structure spectroscopy.