Magnetic anisotropy and spin reorientation effects in Gd/Fe and Gd/(FeCo) multilayers for high density magneto-optical recording

We have investigated the anisotropy behavior and temperature dependent changes of the magnetic anisotropy in Gd/Fe and Gd/(FeCo) multilayers. The spin reorientation effects are very important for the super resolution readout in new methods for high-density magneto-optical recording. Gd/(Fe, Co) multilayered films are a good alternative to the common Gd(Fe, Co) alloy films, because the magnetic anisotropy and also spin reorientation effects can be comfortably adjusted by varying the interface and volume anisotropy components and the composition using experimental parameters such as the periodicity λ=t_Gd+t_TM [t_Gd,t_TM: tne sublayer thicknesses of the Gd and transition metal Fe, FeCo (TM)] and the ratio of the sublayer thicknesses t_Gd/t_TM. We have found the mechanisms for spin reorientation, which are explained qualitatively with a new model.