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Thin ferromagnet/heavy metal multilayer films are considered as prospective media for a magnetic recording and Co/Pd films are a good example of such materials. In this work, the magnetic properties and micromagnetic structure of Co/Pd multilayer films are studied with different bilayer thicknesses ([Co(0.3 × t nm)/Pd(0.5 × t nm)]10), but with the same ratio Co versus Pd. Transmission electron microscope and X‐ray diffraction studies allow authors to suppose that the investigated films are highly mixed alloys. Magnetic force microscopy and Lorentz transmission electron microscopy showed the presence of various micromagnetic features in the films. Along with skyrmions that are well‐known magnetic topological artifacts some new features are revealed, which are interpreted as 360° domain walls, skyrmioniums and the combination of the above two. It is found that the type and density of micromagnetic features strongly depend on the bilayer thickness parameter (t). The effect is associated with the peculiarities of interfacial magnetic interactions in the samples with highly mixed interfaces. The tooling coefficient represents a useful tool of the electron beam evaporation technique enabling wide manipulation of micromagnetic particles, in particular, skyrmioniums that are currently considered a prospective media for current driven magnetic recording. [ABSTRACT FROM AUTHOR]

We have investigated the magnetic properties and micromagnetic structure of multilayer Co/Pt films with the variation of bilayer thickness ([Co(0.3 × t nm)/Pt(0.5 × t nm)] 10). The films represent Co-Pt alloys with periodic Co vs Pt composition. The magnetic force microscopy and Lorentz transmission electron microscopy have demonstrated the presence of N é el-type skyrmions in the films. The density of skyrmions was found to be strongly dependent on the bilayer thickness parameter (t). The effect is attributed to Dzyaloshinskii–Moriya interaction which is known to be strongly dependent on the regularities of magnetic and nonmagnetic layers alternation. We emphasize that the investigated system represents an intermediate case between unalloyed multilayer films and uniformly mixed alloys. Despite that it demonstrates similar micromagnetic behavior with skyrmion density very well controllable by modulation of technological parameters. • Neel-type skyrmions are formed in multilayer Co/Pt films with varying bilayer thickness and diffuse Co/Pt interface. • Skyrmion density is well correlated with Dzyaloshinskii-Moriya interaction constant. • Both skyrmion density and Dzyaloshinskii–Moriya interaction constant are strongly dependent on the bilayer thickness parameter. [ABSTRACT FROM AUTHOR]