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Topological defects in flat nanomagnets: the magnetostatic limit

G. -W. Chern·H. Youk·O. Tchernyshyov
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Abstract

We discuss elementary topological defects in soft magnetic nanoparticles in the thin-film geometry. In the limit dominated by magnetostatic forces the low-energy defects are vortices (winding number n = +1), cross ties (n = -1), and edge defects with n = -1/2. We obtain topological constraints on the possible composition of domain walls. The simplest domain wall in this regime is composed of two -1/2 edge defects and a vortex, in accordance with observations and numerics.

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G. -W. Chern, H. Youk, O. Tchernyshyov. 2005-08-31. Topological defects in flat nanomagnets: the magnetostatic limit. https://doi.org/10.1063/1.2168439

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