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Fractional vortices and composite domain walls in flat nanomagnets

Oleg Tchernyshyov·Gia-Wei Chern
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Abstract

We provide a simple explanation of complex magnetic patterns observed in ferromagnetic nanostructures. To this end we identify elementary topological defects in the field of magnetization: ordinary vortices in the bulk and vortices with half-integer winding numbers confined to the edge. Domain walls found in experiments and numerical simulations in strips and rings are composite objects containing two or more of the elementary defects.

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Oleg Tchernyshyov, Gia-Wei Chern. 2005-09-11. Fractional vortices and composite domain walls in flat nanomagnets. https://doi.org/10.1103/physrevlett.95.197204

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