在反铁磁道交叉点中,来自反铁磁破坏对称性的反铁磁体的大旋转极化
Chung-Tao Chou1,2, Supriya Ghosh3, Brooke C McGoldrick2
1Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nature communications
|September 7, 2024
概括
反铁磁自旋电子装置是有希望的,但它们的自旋偏振不清楚. 这项研究表明,单个反铁磁电极 (Mn3Sn) 的旋转极化显著,在不对称的连接处实现了高道磁阻.
科学领域:
- 这就是Spintronics.
- 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
背景情况:
- 高效的磁性状态检测对于反铁磁自旋电子设备至关重要.
- 关于反铁磁道连接的先前研究主要使用相同的电极,限制了对净旋转偏振的理解.
- 由于磁化消失,反铁磁体 (AFM) 作为旋转偏振器或探测器的潜力仍然不确定.
研究的目的:
- 从单个反铁磁电极实验研究自旋偏振道运输.
- 为了确定反铁磁体是否可以为自旋电子应用提供有限净自旋偏振.
- 用一个AFM和一个铁磁电极制造和描述不对称的道结口.
主要方法:
- 使用Mn3Sn (AFM) 和CoFeB (FM) 电极制造单面抗铁磁道连接点.
- 在冷温度 (10K) 下测量道磁阻力 (TMR).
- 从AFM层通过FM层检测自旋极化道传输.
主要成果:
- 在非对称的AFM道交叉点在10K时观察到高TMR (>100%).
- 从Mn3Sn证明了显著的有效旋转极化,尽管它的磁化接近于零.
- 结果与非对线AFM中对称性破裂升起旋转退化的理论预测一致.
结论:
- 抗铁磁材料,特别是Mn3Sn,可以表现出相当大的旋转极化.
- 不对称的道连接是有效的检测自旋极化运输从AFM.
- 这项工作提供了强有力的实验证据,证明由反铁磁铁可实现的自旋偏振电传输.
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