Skyrmions are emerging topological spin structures that are potentiallyrevolutionary for future data storage and spintronics applications. Theexistence and stability of skyrmions in magnetic materials is usuallyassociated to the presence of the Dzyaloshinskii-Moriya interaction (DMI) inbulk magnets or in magnetic thin films lacking inversion symmetry. While somemethods have already been proposed to generate isolated skyrmions in thin filmswith DMI, a thorough study of the conditions under which the skyrmions willremain stable in order to be manipulated in an integrated spintronic device arestill an open problem. The stability of such structures is believed to be aresult of ideal combinations of perpendicular magnetic anisotropy (PMA), DMIand the interplay between geometry and magnetostatics. In the present work weshow some micromagnetic results supporting previous experimental observationsof magnetic skyrmions in spin-valve stacks with a wide range of DMI values.Using micromagnetic simulations of cobalt-based disks, we obtain the magneticground state configuration for several values of PMA, DMI and geometricparameters. Skyrmion numbers, corresponding to the topological charge, arecalculated in all cases and confirm the occurrence of isolated, stable, axiallysymmetric skyrmions for several combinations of DMI and anisotropy constant.The stability of the skyrmions in disks is then investigated under magneticfield and spin-polarized current, in finite temperature, highlighting thelimits of applicability of these spin textures in spintronic devices.
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