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在RuO_{2}中,将反向磁变旋分裂效应与反向旋霍尔效应分离
Ching-Te Liao1, Yu-Chun Wang1, Yu-Cheng Tien1
1Department of Physics, <a href="https://ror.org/05bqach95">National Taiwan University</a>, Taipei 10617, Taiwan.
Physical review letters
|August 19, 2024
概括
变磁,一种新的磁性状态,表现出独特的旋转分裂效应. 研究人员观察并量化了RuO2薄膜中的反转磁转分裂效应 (IASSE),将其与旋转霍尔效应区分开来.
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:
- 变磁是一种在补偿的对直线抗铁磁体中出现的新型磁性状态,呈现出铁磁体类的时间逆转对称性破坏.
- 变磁自旋分裂效应 (ASSE) 产生横向自旋电流,但在实验上很难将其与自旋霍尔效应隔离.
- 对尼尔载体的控制是至关重要的,但很困难,阻碍了ASSE观测.
研究的目的:
- 实验检测和表征反变磁材料中的反变磁自旋分裂效应 (IASSE).
- 为了区分IASSE与反旋转霍尔效应 (ISHE).
- 通过控制 Néel 矢量对齐,建立一个用于定量研究 ASSE/IASSE 的方法.
主要方法:
- 从伊特铁石榴石中利用热旋注入到表轴RuO2薄膜中.
- 通过测量旋转到充电转换来检测到IASSE.
- 通过改变 RuO2 晶度来操纵 Néel 矢量域.
主要成果:
- 观察到RuO2薄膜中的IASSE与ISHE相反的标志.
- 它将IASSE的效率量化为ISHE效率的70%左右.
- 证明ASSE/IASSE只能在与对齐的Néel向量中观察到.
结论:
- 成功检测和描述IASSE,提供了对变磁自旋分裂效应的实验证据.
- 建立了一种方法,通过控制 Néel 矢量域来明确研究 ASSE/IASSE.
- 这些发现为改变磁性的基本物理及其在自旋电子学中的潜在应用提供了重要的见解.
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