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arXiv · 2412.19077

Extremely Large Anisotropy of Effective Gilbert Damping in Half-Metallic CrO2

Liangliang Guo·Ranran Cai·Zhenhua Zhang·Wenyu Xing·Weiliang Qiao·Rui Xiong·Zhihong Lu·Xincheng Xie·Wei Han
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Abstract

Half-metals are a class of quantum materials with 100% spin-polarization at the Fermi level and have attracted a lot of attention for future spintronic device applications. CrO2 is one of the most promising half-metal candidates, for which the electrical and magnetic properties have been intensively studied in the last several decades. Here, we report the observation of a giant anisotropy (~1600%) of effective Gilbert damping in the single crystalline half metallic (100)-CrO2 thin films, which is significantly larger than the values observed on conventional ferromagnetic Fe and CoFe thin films. Furthermore, the effective Gilbert damping exhibits opposite temperature-dependent behaviors below 50 K with magnetic field along [010] direction and near [001] direction. These experimental results suggest the strong spin-orbit coupling anisotropy of the half-metallic CrO2 and might pave the way for future magnonic computing applications.

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Liangliang Guo, Ranran Cai, Zhenhua Zhang, Wenyu Xing, Weiliang Qiao, Rui Xiong, Zhihong Lu, Xincheng Xie, Wei Han. 2024-12-26. Extremely Large Anisotropy of Effective Gilbert Damping in Half-Metallic CrO2. https://doi.org/10.1021/acs.nanolett.4c05630.

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