光学控制旋转翻转和间位旋转转移之间的竞争,在小于100 fs的时间尺度上的Heusler半金属中
Sinéad A Ryan1, Peter C Johnsen1, Mohamed F Elhanoty2
1JILA, University of Colorado Boulder, 440 UCB, Boulder, CO 80309, USA.
Science advances
|November 10, 2023
概括
用光直接操纵旋转提供了一条通往节能设备的途径. 这项研究使用先进的探测器在Co2MnGa中解开了超快的旋转转移和旋转翻转过程,揭示了关键动态.
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
- 超快的磁力 超快的磁力
背景情况:
- 使用光直接操纵电子自旋对于开发超快,节能的电子设备至关重要.
- 了解磁合金中超快激光激发背后的微观机制是复杂的.
- 像Co2MnGa这样的Heusler化合物由于强烈的光诱导旋转效应,对旋转应用具有前景.
研究的目的:
- 为了研究和区分竞争的超快光诱导旋转动力学在Heusler化合物Co2MnGa.
- 阐明同位点Co-Co旋转转移,间位点Co-Mn旋转转移和旋转轨道合介导的旋转翻转之间的相互作用.
- 提供微观解释的激光诱导磁化动态在sub-100-femtosecond时间尺度.
主要方法:
- 利用特定元素的极紫外线高波光谱仪进行探测.
- 使用时间依赖密度函数理论 (TD-DFT) 进行理论分析.
- 测量Co和Mn亚平面的M边缘的动态磁性不对称性.
主要成果:
- 在Co2MnGa.成功地解开了三种不同的超快速光诱导过程.
- 确定了Co-Co和Co-Mn旋转转移以及旋转翻转的相对贡献.
- 揭示了激光激发过程中这些过程的能量和时间依赖的优势.
结论:
- 综合实验和理论方法提供了对磁合金中的超快旋转动态的全面了解.
- 这项工作为控制超高速时间尺度上的磁化提供了关键的见解.
- 这些发现为设计下一代超快速自旋电子设备铺平了道路.
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