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Curvature-stabilized skyrmions with angular momentum

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Abstract

We examine skyrmionic field configurations on a spherical ferromagnet with large normal anisotropy. Exploiting variational concepts of angular momentum, we find a new family of localized solutions to the Landau–Lifshitz equation that are topologically distinct from the ground state and not equivariant. Significantly, we observe an emergent spin–orbit coupling on the level of magnetization dynamics in a simple system without individual rotational invariance in spin and coordinate space.

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Acknowledgements

We are indebted to Stavros Komineas for pointing out the relevance of angular momenta in the context of chiral magnetism and for valuable discussions on the subject matter.

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Correspondence to Christof Melcher.

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This work is supported by Deutsche Forschungsgemeinschaft (DFG Grant No. ME 2273/3-1).

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Melcher, C., Sakellaris, Z.N. Curvature-stabilized skyrmions with angular momentum. Lett Math Phys 109, 2291–2304 (2019). https://doi.org/10.1007/s11005-019-01188-6

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Keywords

  • Magnetic skyrmions
  • Landau–Lifshitz equation
  • Angular momentum

Mathematics Subject Classification

  • 49S05
  • 35Q60
  • 37K05
  • 82D40