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arXiv · 1809.01247

Twisted domain walls and skyrmions in perpendicularly magnetized multilayers

Ivan Lemesh·Geoffrey S. D. Beach
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Abstract

We present an analytical theory to describe three-dimensional magnetic textures in perpendicularly magnetized magnetic multilayers that arise in the presence of magnetostatic interactions and the Dzyaloshinskii-Moriya interaction (DMI). We demonstrate that domain walls in multilayers develop a complex twisted structure, which persists even for films with strong DMI. The origin of this twist is surface-volume stray field interactions that manifest as a depth-dependent effective field whose form mimics the DMI effective field. We find that the wall twist has a minor impact on the equilibrium skyrmion or domain size, but can significantly affect current-driven dynamics. Our conclusions are based on the derived analytical expressions for the magnetostatic energy and confirmed by micromagnetic simulations.

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Ivan Lemesh, Geoffrey S. D. Beach. 2018-09-04. Twisted domain walls and skyrmions in perpendicularly magnetized multilayers. https://doi.org/10.1103/physrevb.98.104402

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