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在Co₅₀Pt₅₀合金中的五秒充电和旋转动态

Martin Pavelka¹, Simon Marotzke, Ru-Pan Wang²

¹Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden.

Structural dynamics (Melville, N.Y.)

|April 28, 2025

概括

像自由电子激光器这样的先进的X射线源揭示了超快的磁性材料动力学. 五秒的X射线脉冲显示了与CoPd相似的CoPt合金去磁化,与旋转轨道合差异有关.

科学领域:

材料科学材料科学材料科学
凝聚物质物理学凝聚物质物理学
超快速光谱法超快速光谱法

背景情况:

先进的X射线源对于研究磁性材料中的动态过程至关重要.
X射线自由电子激光器 (XFEL) 能够同时观察秒电子和自旋系统的演变.
短暂的X射线吸收光谱学和X射线磁性循环二元化解决了对光学刺激的自旋分裂价值状态反应.

研究的目的:

为了研究激光激发的白金 (CoPt) 合金的五秒钟消磁动力学.
为了利用FLASH自由电子激光器的循环极化超短软X射线脉冲.
在Cobalt L3边缘吸收处探测动力学.

主要方法:

五秒钟时间分辨率的X射线磁圆二元化 (XMCD).
柔软的X射线脉冲来自FLASH的螺旋式后燃机波动器.
Co L3-边缘吸收光谱学.

主要成果:

在激光激发的CoPt合金中观察到femtosecond脱磁动态.
在CoPt的Co3d状态中发现了相似的去磁化,尽管与CoPd相比,激发力较弱.
将发现归因于3d-4d和3d-5d元素之间自旋轨道合的差异.

结论:

旋转轨道合在磁合金的超快速去磁化动态中起着至关重要的作用.
CoPt合金表现出强大的去磁行为,受到电子结构和元素配对的影响.
五秒X射线技术为控制磁性材料反应的基本机制提供了前所未有的洞察力.

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