Synthesis of thin-film magnetic structures for spin-orbitronics

Multilayer metallic nanostructures are promising not only for the creation of spin valves based on the giant magnetoresistance effect, but also for studying the nature of topological magnetism aiming to creation, for example, new nanoscale devices for storing and transmitting data based on magnetic skyrmions. Actual problem remains the development of methods for the synthesis and configuration of thin-film nanostructures and control over spin textures in them under the influence of electric and spin currents arising due to the spin Hall effect, with external fields applied. In this work the metallic thin film nanostuctures of the ferromagnetic/heavy metal type were obtained by the magnetron sputtering method: Ru(10 nm)/Co(0.8)/Ru(2), Ru(10)/Co(0.8)/Ru(2)/W(4), Pt(5)/Co(0.8)/MgO(2)/Pt(2), Pt(15)/Co(0.8)/MgO(2)/Pt(2). Electrical contacts and Hall structures with different widths of the current-carrying bridge were fabricated on the obtained samples using electron beam and photolithography. Based on experimental data obtained from a vibrating magnetometer, the magnetic parameters of each sample were calculated, including saturation magnetization, energy and field of magnetic anisotropy, and coercive force, depending on the type of ferromagnetic layer and heavy metal layer. The domain structure of the samples was determined using Kerr microscopy. Electrical resistance modeling was performed, and critical current values and maximum current density in nanostuctures were estimated. It was shown that all obtained thin-film samples have perpendicular magnetic anisotropy and can be used to study current-induced phenomena and spin transfer processes in nanostuctures.

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