在铁磁-半导体量子井混合结构中的通用磁性近距离效应
I V Kalitukha1,2, E Yalcin1, O S Ken1,2
1Experimentelle Physik 2, Technische Universität Dortmund, 44227 Dortmund, Germany.
The Journal of chemical physics
|July 5, 2023
概括
远程磁性近距离效应是混合铁磁半导体系统中的普遍现象. 这种在各种磁性材料中观察到的效应使新的自旋电子设备成为可能.
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
- 这就是Spintronics.
背景情况:
- 混合铁磁半导体系统由于磁性和半导体自旋系统的合,具有独特的特性.
- 长距离的磁性近距离效应超出载波函数重叠,由p-d交换相互作用和奇拉声子介导.
- 了解这种效应对于推进自旋电子设备技术至关重要.
研究的目的:
- 为了证明各种混合结构中远程磁性近距离效应的普遍性.
- 为了研究使用介电或半金属铁磁体 (旋NiFe2O4,磁铁Fe3O4) 和CdTe量子井的系统中的近距离效应.
- 探索近距离效应的动态及其对设备应用的潜力.
主要方法:
- 使用铁磁铁 (Fe3O4,NiFe2O4) 和由 (Cd,Mg) Te屏障隔离的CdTe量子井制造混合结构.
- 使用光发光的光学特征来观察由磁性近距离效应引起的圆极化.
- 对近距离效应动态的分析,包括再组合诱导的动态极化.
主要成果:
- 证明了跨不同磁性材料和屏障组成的远程磁性近距离效应的普遍性.
- 观察到的近距离效应表现为光发光循环极化,起源于铁磁铁本身.
- 通过动态极化分析测量了磁铁结构中的交换常数 (Δexch ≈ 70 μeV).
结论:
- 远程磁性近距离效应是各种铁磁半导体混合系统中的普遍现象.
- 由内在磁性元件驱动的观察到的效应为开发新型自旋电子设备提供了途径.
- 对这种相互作用的电气控制对与当前电子相兼容的低压自旋电子应用具有前景.
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