Gauged Sigma Models and Magnetic Skyrmions

Bernd Schroers

doi:10.21468/scipostphys.7.3.030

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arXiv · 1905.06285

Gauged Sigma Models and Magnetic Skyrmions

Bernd Schroers

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Abstract

We define a gauged non-linear sigma model for a 2-sphere valued field and a $SU(2)$ connection on an arbitrary Riemann surface whose energy functional reduces to that for critically coupled magnetic skyrmions in the plane, with arbitrary Dzyaloshinskii-Moriya interaction, for a suitably chosen gauge field. We use the interplay of unitary and holomorphic structures to derive a general solution of the first order Bogomol'nyi equation of the model for any given connection. We illustrate this formula with examples, and also point out applications to the study of impurities

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Bernd Schroers. 2019-05-15. Gauged Sigma Models and Magnetic Skyrmions. https://doi.org/10.21468/scipostphys.7.3.030

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