Magnetic Anisotropy And Magneto Optical Property Of Fe/Co/Cu(001): Role Of The Interface Alloy

Using the full potential linearized augmented plane wave (FLAPW) method, we have investigated the role of interface alloy type on the thickness dependent magnetic properties of ultrathin Fe/Co/Cu(001) films. We have observed that the Co underlayer induces an antiferromagnetic (AFM) state in Fe/Co/Cu(001) film, but the position of AFM layer is strongly sensitive to both Fe and Co coverage. It is found that the magnetic anisotropy of Fe/Co/Cu alloy films is significantly influenced by the alloy type and the Fe film thickness. For instance, a thickness-dependent spin reorientation transition from in-plane to perpendicular to the film surface or vice versa is observed in CoFe alloy configuration whereas the perpendicular magnetization is always achieved in CuCo alloy. In particular, a large perpendicular magnetic anisotropy energy (MAE) about 270 mu eV//atom at 4 ML Fe thickness is observed in the CuCo alloy. In addition, we find that the magnitude of Kerr rotation angle in the presence of antiferromagnetic layer is greatly suppressed compared with that of fully ferromagnetic films.