Dependence of Atomic Thickness on Interfacial Conditions and Magnetocrystalline Anisotropy in SmCo5/Sm2Co17 Multilayer

We have performed first-principles calculations to study the interfacial exchange coupling and magnetocrystalline anisotropy energy in a SmCo5/Sm2Co17 multilayer model system. The phase of SmCo5 and Sm2Co17 stacking along (0001) direction are structurally well matched. The atomic structure, including the alignment and the separation between layers, were firstly optimized. Then the non-collinear magnetic structures were calculated to explore the exchange coupling across the interface and the variation of magnetocrystalline anisotropy energy. We found that the inter-phase exchange coupling strength, rotating behavior and magnetocrystalline anisotropy strongly depend on the atomic thickness of the SmCo5 and Sm2Co17 phase.