Methods of modulation of micromagnetic characteristics of multilayer thin-film systems [Co/Pt]

Multilayer magnetic films were formed, representing 10 alternating layers of Co and Pt with a thickness of 3 and 5 $\mathring{\mathrm{A}}$, respectively ([Co(3)Pt(5)]$_{10}$). Two technological modifications of the multilayer Co/Pt structure are considered, one of which (doubling the thickness of the Co and Pt layers in one of the ten bilayers) allows for small adjustments, and the other (increasing the thickness of the Co layer by 3.5 times in one of the 10 bilayers) significantly changes the micromagnetic parameters: the density of skyrmions in a magnetized film in a zero magnetic field. The effect obtained is associated with modulations of the degree of mixing between the Co and Pt layers, which in the first case lead to some change in the composition of the Co$_x$Pt$_{1-x}$ solid solution in the center of the multilayer structure, and in the second case to the formation of an unmixed Co layer in the center of the structure; the boundaries between this layer and the Co$_x$Pt$_{1-x}$ solid solution provide a significant change in magnetic properties.