Temperature dependencies of magnetization in the Co/Cu (111) superlattices

It was found that temperature dependencies of magnetization in the Co/Cu (111) superlattices contain ferromagnetic and paramagnetic contributions. Samples of the [Co(8 Å)/Cu(d Cu)]20 (d Cu = 9–1 Å) series were grown on mica by magnetron sputtering upon a pseudomorphic growth of Co and Cu layers. They have a polycrystalline structure with a grain size of 80–100 Å. Estimates show that the paramagnetic magnetization part is formed by ∼48% of Co atoms contained in a sample. It is assumed that the most probable mechanism of formation of the paramagnetic phase is related to diffusion processes in an interface between grains.