在合成反铁磁铁中,高效率和灵活调制Spintronic Terahertz发射器
Yiwen Song1, Zhihao Ji1, Yu Zhang1
1Shanghai Ultra-Precision Optical Manufacturing Engineering Research Center and Key Laboratory of Micro and Nano Photonic Structures (MOE), School of Information Science and Technology, Fudan University, Shanghai 200433, China.
ACS applied materials & interfaces
|October 26, 2023
概括
合成反铁磁体 (SAF) 增强了太赫兹 (THz) 辐射. 具有主导层的不对称SAF结构产生更强的THz场,为THz设备提供更好的控制.
科学领域:
- 这就是Spintronics.
- 太赫兹 (THz) 科学科学
- 材料科学 材料科学 材料科学
背景情况:
- 螺旋式太赫兹 (THz) 发射器使用合成反铁磁体 (SAF) 来增强THz功率.
- 了解层间合和净磁化效应对于基于SAF的THz设备优化至关重要.
- 目前的知识差距阻碍了THz发射器的性能改进和实际应用.
研究的目的:
- 在Pt/CoFe/Ru/CoFe/Pt薄膜中研究 femt秒激光诱导的THz辐射.
- 澄清层间交换合和净磁化对THz发射特性的影响.
- 确定最佳的SAF结构,以增强THz的产生.
主要方法:
- 制造不同厚度的Pt/CoFe/Ru/CoFe/Pt多层薄膜.
- 反铁磁 (AF) 合和层间交换场 (H_ex) 的表征.
- 在秒激光激发下测量THz发射幅度和极性.
主要成果:
- 在特定的Ru厚度范围内观察到抗铁磁合,在t_Ru = 0.4 nm时具有更高的合场.
- 强大的THz振幅与强大的AF合相关.
- 在对称的SAF中,由于非对线磁化,随着Ru厚度的降低,THz排放量减少.
- 具有主导铁磁层的不对称SAF结构显示显著增强THz电场,可控制极性和强度.
- THz排放的温度依赖性有所变化,在具有微不足道的二次方程合的样本中,在较低的温度下强度增加.
结论:
- 不对称的SAF结构优于补偿的结构,用于增强THz排放.
- 控制层间合和磁化是优化THz输出的关键.
- 结果为设计高性能旋转式THz发射器提供了洞察力.
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