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arXiv · 2102.13126

Stability of highly-twisted Skyrmions from contact topology

Yichen Hu·Thomas Machon
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Abstract

We describe a topological protection mechanism for highly-twisted two-dimensional Skyrmions in systems with Dyloshinskii-Moriya (DM) coupling, where non-zero DM energy density (dubbed "twisting energy density") acts as a kind of band gap in real space, yielding an N invariant for highly twisted Skyrmions. We prove our result through the application of contact topology by extending our system along a fictitious third dimension, and further establish the structural stability of highly-twisted Skyrmions under arbitrary chirality-preserving distortions. Our results apply for all two-dimensional systems hosting Skyrmion excitations including spin-orbit coupled systems exhibiting quantum Hall ferromagnetism.

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Yichen Hu, Thomas Machon. 2021-02-25. Stability of highly-twisted Skyrmions from contact topology. https://arxiv.org/abs/2102.13126

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