Structural and magnetic characteristics of the Co/Cu/Co thin-film systems
The results on investigation of structural and magnetic characteristics of Co/Cu/Co thin-film systems obtained by magnetron sputtering on glass substrates are presented. The thickness of Co layers in all samples is equal to 5 nm and the Cu layer is varied from 0.5 to 4 nm. It is found that the saturation field, HS, oscillates in magnitude with increasing Cu layer thickness with the period of the order of 1 nm. The maximum values of HS are observed for tCu = 1.4, 2.2 and 3.2 nm. The hysteresis loops measured for these samples in a magnetic field applied along the easy magnetization axis have a two-step form, and for other tCu – rectangular one. The obtained results are explained by the presence of exchange coupling between the ferromagnetic layers through a Co spacer and its oscillating behavior with changing tCu.