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arXiv · 1807.05232

Magnon band topology in spin-orbital coupled magnets: classification and application to $\alpha$-RuCl$_3$

Fuyan Lu·Yuan-Ming Lu
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Abstract

In spite of flourishing studies on the topology of spin waves, a generic framework to classify and compute magnon band topology in non-collinear magnets is still missing. In this work we provide such a theory framework, by mapping an arbitrary linear spin wave into a local free-fermion Hamiltonian with exactly the same spectrum, symmetry implementation and band topology, which allows for a full classification and calculation on any topological properties of magnon bands. We apply this fermionization approach to honeycomb Kitaev magnet $\alpha$-RuCl$_3$, and show the existence of topologically protected magnon band crossings, and field-induced magnon Chern bands under small magnetic fields.

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Fuyan Lu, Yuan-Ming Lu. 2018-07-13. Magnon band topology in spin-orbital coupled magnets: classification and application to $\alpha$-RuCl$_3$. https://arxiv.org/abs/1807.05232

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