单层旋转-轨道-扭矩磁化切换由于旋转曲率由微小自发原子移位在韦尔氧化物中产生
Hiroto Horiuchi1, Yasufumi Araki2, Yuki K Wakabayashi3
1Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
Advanced materials (Deerfield Beach, Fla.)
|April 24, 2025
概括
单晶 SrRuO3 薄膜中的微小原子扭曲可以产生相当大的旋转贝里曲率,从而为旋转电子应用提供高效的旋转轨道扭矩 (SOT).
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:
- 旋转贝里曲率是旋转电子学的关键,类似于贝里曲率,但用于旋转.
- 打破反向对称性可以增强旋转贝里曲率和旋转轨道扭矩 (SOT).
- 目前SOT的方法通常依赖于复杂的异构结构,如铁磁/重金属双层.
研究的目的:
- 为了证明SOT诱导的磁化切换在一个单层SrRuO3.3.
- 研究原子扭曲在增强自旋霍尔导电性的作用.
- 探索单晶氧化物在先进的自旋电子设备中的潜力.
主要方法:
- 在SrRuO3薄膜中实验性演示SOT诱导的部分磁化切换.
- 详细的晶体分析以确定微妙的原子移位 (氧八面体旋转).
- 紧密结合计算以建模电子带结构和旋转贝里曲率.
主要成果:
- 在低电流密度 (≈3.1 × 10^6 A cm^-2) 的单晶 SrRuO3 中实现了部分磁化开关.
- 在基板接口附近的氧八面体旋转 (≈5°) 被确定为反向对称性破坏的来源.
- 计算表明,这些旋转会在带交叉处诱导带间隙,显著提高旋转厅导电性.
结论:
- 单晶薄膜中的微小原子位移可以产生强大的内在SOT.
- 由于其可调节带拓,SrRuO3是旋转轨道电子器件的一个有希望的材料.
- 这项工作为新型自旋电子设备设计铺平了道路,利用内在材料特性.
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