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动量空间热点的长距离轨道扭矩
Dongwook Go1,2, Daegeun Jo3, Kyoung-Whan Kim4
1Peter Grünberg Institut and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425 Jülich, Germany.
Physical review letters
|June 30, 2023
概括
我们证明铁磁体的轨道反应可以具有令人惊的长距离,超过旋转脱相长度. 这一发现为轨道电子设备开辟了新的途径,透露了一种独特的轨道扭矩类型.
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.
- 量子力学就是量子力学.
背景情况:
- 铁磁体的轨道反应通常被认为是短距离的,这是由于晶体场效应和轨道火.
- 在铁磁/非磁双层中注入旋转会导致旋转积累和扭矩,由于旋转脱相而迅速衰减.
研究的目的:
- 为了研究铁磁体轨道反应的范围和性质,特别是当电场应用于相邻的非磁层时.
- 探索负责远程轨道效应的潜在机制及其对设备应用的潜在影响.
主要方法:
- 铁磁/非磁双层系统的理论研究.
- 在对非磁层施加的外部电场下的诱导轨道角动量和扭矩的分析.
- 检查晶体对称性和电子带结构在轨道传输中介作用.
主要成果:
- 在铁磁体中证明了相当长的远程诱导轨道角动量,超过了自转脱相长度.
- 他将这种远程行为归因于由晶体对称性强加的近乎退化的轨道特征,为轨道反应创造了"热点".
- 确定了一种独特的轨道扭矩类型,随着铁磁铁的厚度而增加,并且不会受到破坏性干扰.
结论:
- 铁磁体的轨道反应可以非常长距离,与普遍的假设相反.
- 这些发现为轨道运输提供了关键证据,并提出了产生轨道扭矩的新机制.
- 这种远程轨道响应对未来的轨道电子设备应用具有重大潜力.
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