在对直线反铁磁体MnPtt中对尼尔向量的超快控制
Sambhu Jana1,2, Sobhan Subhra Mishra1,2, James Lourembam3
1Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|November 10, 2025
概括
这项研究揭示了交换偏差合的自旋式太赫兹发射器 (EBC-STEs) 中超快反铁磁 (AFM) 磁化动态. 这一突破将AFM从被动组件转变为界面磁性的敏感探头.
科学领域:
- 这就是Spintronics.
- 特拉赫兹 (THz) 光子学
- 抗铁磁 (AFM) 材料是一种抗铁磁材料.
背景情况:
- 交换偏差合的自旋式太赫兹发射器 (EBC-STEs) 传统上使用反铁磁体 (AFM) 作为被动固定层.
- 由于它们的零净磁矩,AFM的超快动态被认为是不可检测的,这限制了它们在太赫兹 (THz) 发射中的作用.
研究的目的:
- 展示一种用于探测和控制EBC-STEs内的AFM中超快磁化动态的新方法.
- 调查EBC-STEs与传统的自旋式太赫兹发射器 (STEs) 相比的稳定性.
主要方法:
- 利用激光诱导的光学扭矩来驱动对直线AFM MnPt中的Neel向量动力学.
- 隔离并检测出来自Pt/MnPt双层倾斜磁矩的明显THz辐射,以探测AFM动态.
- 在光学激发下比较EBC-STEs和传统STEs的稳定性.
主要成果:
- 通过光学扭矩驱动的超快速AFM磁化动力学成功演示和检测.
- 已确认,来自倾斜磁矩的THz发射源自AFM子系统.
- 提供了AFM动态影响EBC-STEsTHz排放的直接证据.
结论:
- 抗铁磁 (AFM) 磁化动态可以在EBC-STEs中直接探测和控制.
- EBC-STEs可以作为界面超快磁性的敏感探头.
- 这项研究释放了反铁磁THz旋转电子的潜力.
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