Analysis of interfacial magnetic anisotropy in Co ∕ Pt and Co ∕ Pd multilayer films

Analysis of Co ∕ Pt and Co ∕ Pd multilayer films was performed to investigate the dependence of interfacial magnetic anisotropy (IMA) and induced magnetization on the thickness of the laminated Pd or Pt layers. For the Co ∕ Pd films, the IMA energy increased as the thickness of the laminated Pd layer was increased up to ∼ 0.8 nm and depended proportionally on the amount of the induced magnetization. This suggests that the whole magnetic moment induced in a few Pd atomic layers contributed to the IMA. In contrast, for the Co ∕ Pt films, this proportional relationship only held when the thickness of the Pt layer was less than ∼ 0.2 nm . Since one Pt monolayer is 0.225 nm thick, the amount of the IMA energy in the Co ∕ Pt films is proportional to the number of Pt-Co atomic contacts. This difference between Co ∕ Pt and Co ∕ Pd multilayer films is attributed to the difference in the latent ferromagnetism between Pt and Pd.