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arXiv · 1705.07353

Thermally Driven Topology in Chiral Magnets

Wen-Tao Hou·Jie-Xiang Yu·Morgan Daly·Jiadong Zang
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Abstract

Chiral magnets give rise to the anti-symmetric Dzyaloshinskii-Moriya (DM) interaction, which induces topological nontrivial textures such as magnetic skyrmions. The topology is characterized by integer values of the topological charge. In this work, we performed the Monte-Carlo calculation of a two-dimensional model of the chiral magnet. A surprising upturn of the topological charge is identified at high fields and high temperatures. This upturn is closely related to thermal fluctuations at the atomic scale, and is explained by a simple physical picture based on triangulation of the lattice. This emergent topology is also explained by a field-theoretic analysis using $CP^{1}$ formalism.

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Wen-Tao Hou, Jie-Xiang Yu, Morgan Daly, Jiadong Zang. 2018-02-26. Thermally Driven Topology in Chiral Magnets. https://doi.org/10.1103/physrevb.96.140403

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