Magnetic properties of FePt thin films with multilayered structure

The structure and magnetic properties of FePt films with multilayered structure have been investigated. Intermediate layer of Cu or Fe/Au was inserted between top and bottom FePt layers. From X-ray diffraction patterns, the (002) fundamental peak and (001) and (003) super lattice peaks of the L1(0) phase have been clearly observed for all the samples. The peak from FePt (200) has begun to observe for FePt/Cu/FePt films at the thickness of more than 3 nm. With increasing the intermediate layer thickness (t), coercivity measured in the direction perpendicular to the film plane was increased. However, an uniaxial magnetocrystalline anisotropy (K-u) was decreased for FePt/Cu/FePt films, while K-u maintains a large value of 4x10(7) (erg/cm(3)) for FePt/Fe/Au/FePt films. It was confirmed that the top FePt layer was grown epitaxially on the intermediate layer of Fe/Au without deterioration of the large K-u.