Growth of thin-film magnetic nanostructures promising for spintronics applications

Abstract

Multilayered metallic nanostructures are promising for the fabrication of spin valves based on the giant magnetoresistive effect and for studies of the nature of topological magnetism, aimed at the development of new nanoscale data storage and transfer devices, e.g. those based on magnetic skyrmions. It is still an important task to develop methods of synthesis and configuration of thin-film nanostructures and control of spin textures in those nanostructures under electric and spin currents generated as a result of the spin Hall effect in external electric fields. Thin-film polycrystalline ferromagnetic / heavy metal Ru(10nm)/Co(0,8)/Ru(2), Ru(10)/Co(0,8)/Ru(2)/W(4), Pt(5)/Co(0,8)/MgO(2)/Pt(2) and Pt(15)/Co(0,8)/MgO(2)/Pt(2) nanostructures have been synthesized using magnetron sputtering. Electric contacts and Hall structures with different conductive bridge thicknesses have been synthesized on the specimens using electron beam photolithography. Experimental vibration magnetometric data have been utilized to calculate magnetic parameters of the specimens, i.e., saturation magnetization, magnetic anisotropy energy and field and coercive force as functions of ferromagnetic and heavy metal layer types. The domain structure of the specimens has been studied using Kerr microscopy. The electrical resistivity has been simulated and the critical current and current density of the nanostructures have been assessed. We show that all the film specimens exhibit perpendicular magnetic anisotropy and can be used in the studies of current-induced phenomena and spin moment transfer processes in nanostructures.