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arXiv · 1705.03397

Topological spin dynamics in cubic FeGe near room temperature

Emrah Turgut·Matthew J. Stolt·Song Jin·Gregory D. Fuchs
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Abstract

Understanding spin-wave dynamics in chiral magnets is a key step for the development of high-speed, spin-wave based spintronic devices that take advantage of chiral and topological spin textures for their operation. Here we present an experimental and theoretical study of spin-wave dynamics in a cubic B20 FeGe single crystal. Using the combination of waveguide microwave absorption spectroscopy (MAS), micromagnetic simulations, and analytical theory, we identify the resonance dynamics in all magnetic phases (field polarized, conical, helical, and skyrmion phases). Because the resonance frequencies of specific chiral spin textures are unique, quantitative agreement between our theoretical predictions and experimental findings for all resonance frequencies and spin wave modes enables us to unambiguously identify chiral magnetic phases and to demonstrate that MAS is a powerful tool to efficiently extract a magnetic phase diagram. These results provide a new tool to accelerate the integration of chiral magnetic materials into spintronic devices.

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Emrah Turgut, Matthew J. Stolt, Song Jin, Gregory D. Fuchs. 2017-05-09. Topological spin dynamics in cubic FeGe near room temperature. https://doi.org/10.1063/1.4997013

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