PERPENDICULAR MAGNETIC-ANISOTROPY OF MULTILAYERS - RECENT INSIGHTS

Extending our understanding of perpendicular magnetic anisotropy (PMA) beyond the phenomenological approach of volume (K-V) and interface an isotropies (K-S) requires caution. Experimentally, many factors such a s roughness, formation of interface alloys, or patchiness of ultrathin layers may cause a reduction in PIMA. Where stresses are present in m ultilayer growth, these may, under particular circumstances, contribut e to both K-V and K-S, as demonstrated for the Cu/Ni/Cu system. Theore tically, the difficulty in modelling incoherently grown materials prev ents a detailed quantitative comparison with most experimental systems , so that an evaluation of the underlying approximations common to all of the quantitative theoretical studies becomes very difficult.