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arXiv · 1606.09249

Damped Topological Magnons in the Kagomé-Lattice Ferromagnets

A. L. Chernyshev·P. A. Maksimov
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Abstract

We demonstrate that interactions can substantially undermine the free-particle description of magnons in ferromagnets on geometrically frustrated lattices. The anharmonic coupling, facilitated by the Dzyaloshinskii-Moriya interaction, and a highly-degenerate two-magnon continuum yield a strong, non-perturbative damping of the high-energy magnon modes. We provide a detailed account of the effect for the $S=1/2$ ferromagnet on the kagomé lattice and propose further experiments.

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A. L. Chernyshev, P. A. Maksimov. 2016-10-20. Damped Topological Magnons in the Kagomé-Lattice Ferromagnets. https://doi.org/10.1103/physrevlett.117.187203

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