Perpendicular magnetic anisotropy in Pt/Fe multilayers

Perpendicular magnetic anisotropy (K⊥) and related magnetic properties in Pt/Fe multilayers [compositionally modulated multilayer films (CMFs)] are investigated. It is found that Pt/Fe CMFs with about an 18‐A Pt layer and Fe layer below 5 A become perpendicularly magnetized films. Surface magnetic anisotropy (Ks) and volume anisotropy (Kv) are 0.46 erg/cm2 and about − 2 × 107 erg/cm3 at room temperature, respectively. The Ks is almost equivalent to that of Pt/Co CMFs and increases with decreasing temperature. The absolute value of Kv, however, is much larger than that of the Pt/Co system. The effective magnetic anisotropy (K⊥ eff) of [Fe(4.7 A)/Pt(18.5 A)]80 CMF changes from positive to negative at T≂200 K with decreasing temperature.