Reversal in magnetic anisotropy of (100)Cu-Ni superlattices

Abstract

(100)Cu-Ni superlattices with the same Ni thickness, 25 Å, and different Cu thickness, 25-100 Å, have been deposited on (100)Si using a 1000 Å (100)Cu layer as the seed. Magnetic measurement shows a reversal in anisotropy between the in-plane and normal-to-plane magnetization for the samples with 100 Å Cu layers, with the normal-to-plane one being much larger. The reversal is similar to, but less dramatic than the previously observed one for the single Ni layers sandwiched between two 1000 Å Cu layers. The difference is attributed to a smaller lattice distortion of Ni in the Cu-Ni superlattice structures with much thinner Cu layers. The (111)Cu-Ni superlattices of identical composition show signs of changing anisotropy; the in-plane magnetization still remains the larger one for the structures with 100 Å Cu layers. © 1991.