Influence of the anisotropy and the DMI constant on the magnetic skyrmions in elliptical and rectangular-shaped nanomagnets

Abstract

Micromagnetic simulations have been used to study the influence of the anisotropy (K U ) and Dzyaloshinskii-Moriya interaction (DMI) constant on the stability and size of magnetic skyrmions in elliptical and rectangular-shaped nanostructures, in order to understand the role of the geometry on magnetic skyrmions. In order to compare the changes in the internal magnetic states for the elliptical and rectangular nanostructures, the lengths of the major and minor sides and axes of the rectangle and ellipse, respectively, are considered equal in values. For both types of geometries, micromagnetic simulations clearly demonstrate the influence of the K U and DMI constant on the stability and size of magnetic skyrmions. A plot of K U versus DMI for the range of 1.10 to 1.40 MJ/m3 and 0 to 6.0 mJ/m2, respectively, shows that the elliptical nanomagnets have a higher range of K U and DMI values to stabilize the skyrmions. It is also observed that for K U and DMI values of 1.30 MJ/m3 and 2.0 mJ/m2, respectively, the diameter of the skyrmions increases with the minor to the major length of the ellipse. These results have been explained in terms of the interplay between the different energies and the geometry of the nanostructure.