Influence of the Dzyaloshinskii-Moriya interaction on vortex states in magnetic nanodisks

Abstract

Curling magnetic vortices with chiral rotation sense and polarity of the core magnetization can exist in magnetic circular nanostructures. Broken mirror symmetry at surfaces/interfaces of magnetic nanostructures induces chiral Dzyaloshinskii-Moriya interactions which may strongly affect the magnetic properties. Using a micromagnetic approach, we investigate the influence of these chiral interactions on the vortex states in magnetic nanodisks. We calculate numerically the shape, size, and stability of the vortices in equilibrium as functions of magnetic field and the material and geometrical parameters. As a result, under the influence of the chiral magnetic interactions vortices of opposite chirality should have different sizes. We provide detailed numerical analysis of this effect, which can be applied to measure the strength of the induced Dzyaloshinskii-Moriya coupling in magnetic thin film elements.