在kagome铁磁体中发现了太赫兹频率的轨道合磁子
Mengqian Che1, Weizhao Chen2, Maoyuan Wang3
1State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China.
Science advances
|July 4, 2025
概括
研究人员在kagome铁磁磁体中发现了与轨道磁矩相关的太赫兹磁子. 这些发现为高速的太赫兹旋转电子学开辟了新的途径.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 量子磁力 量子磁力 量子磁力
背景情况:
- 磁子是自旋波的量子,在铁磁材料中通常在千兆赫兹范围内运行.
- 理论预测表明,磁子与轨道磁矩相关,但实验观测仍然很困难.
- 拓式Kagome铁磁铁具有独特的磁性.
研究的目的:
- 通过实验观察和描述与轨道磁时相结合的太赫兹磁子.
- 研究Co3Sn2S2在新型自旋电子应用中的潜力.
主要方法:
- 时间分辨率的克尔旋转光谱学被用来检测磁共振.
- 在低温 (6K) 进行测量,以识别不同的太赫兹模式.
主要成果:
- 在Co3Sn2S2.2.中,在0.61 THz和0.49 THz时分别发现了两个不同的太赫兹磁共振.
- 这些共振归因于局部自旋和轨道磁矩之间的强合.
- 观察到的马格农频率超过了通常在铁磁体中发现的频率,这是由于强大的磁晶异质性.
结论:
- 这一发现证实了铁磁体中存在非常规的轨道合磁子.
- Co3Sn2S2成为开发高速太赫兹自旋电子设备的关键材料.
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