Thickness and strain dependent magnetic anisotropy of ultrathin Fe/Ni films

Using the full potential linearized augmented plane wave method (FLAPW), the magnetic properties of ultrathin Fe/Ni films grown on Cu(0 0 1) surface have been investigated. We have varied both Ni and Fe film thicknesses and also have explored the strain effect on the magnetic anisotropy. For surface Fe atom, a typical surface enhancement of spin magnetic moment has been observed while the magnetic moments of other constituents are rather insensitive to the strain effect. Nonetheless, we have realized that the direction of magnetization is significantly affected by the strain factor. For instance, the Fe/Ni films always have perpendicular magnetization provided that they are grown on Cu(0 0 1) lattice constant. However, we have obtained a spin reorientation transition (SRT) phenomenon in the presence of strain effect.