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arXiv · 2302.04846

Chiral and flat-band magnetic cluster excitations in a ferromagnetic kagome metal

S. X. M. Riberolles·Tyler J. Slade·Tianxiong Han·Bing Li·D. L. Abernathy·P. C. Canfield·B. G. Ueland·P. P. Orth·Liqin Ke·R. J. McQueeney
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Abstract

TbMn6Sn6 is a metallic ferrimagnet that displays signatures of band topology arising from a combination of uniaxial ferromagnetism and spin-orbit coupling within its Mn kagome layers. Whereas the low energy magnetic excitations can be described as collective spin waves using a local moment Heisenberg model, sharply defined optical and flat-band collective magnon modes are not observed. In their place, we find overdamped chiral and flat-band spin correlations that are localized to hexagonal plaquettes within the kagome layer.

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S. X. M. Riberolles, Tyler J. Slade, Tianxiong Han, Bing Li, D. L. Abernathy, P. C. Canfield, B. G. Ueland, P. P. Orth, Liqin Ke, R. J. McQueeney. 2023-02-06. Chiral and flat-band magnetic cluster excitations in a ferromagnetic kagome metal. https://doi.org/10.1038/s41467-024-45841-8

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