Magnetic Anisotropy Studies in Ce/Fe and U/Fe Multilayers

Abstract

Multilayer samples of Ce/Fe, fabricated by sputtering and characterized by X‐ray diffraction and reflectivity were studied by polarized neutron reflectivity and Mössbauer spectroscopy. Corresponding studies on sputtered U/Fe multilayers have been initiated. In Fe/Ce a paramagnetic phase, identified as amorphous Fe was observed at Fe thicknesses below 20 Å. Perpendicular magnetic anisotropy was observed for Fe thicknesses below 17 Å and studies in applied fields enabled magnetic anisotropies to be evaluated for Fe thicknesses up to 40 Å. The Ce/Fe interface anisotropy was evaluated as Ks = (0.98 ± 0.15) × 10—3 Jm—2, among the largest values reported. Neutron reflectivity results did not observe magnetic moments on Ce layers. Preliminary measurements on U/Fe multilayers have not observed induced moments on the U layers.