垂直磁化的无场旋转轨道切换是由于位移诱导的平面内对称性破坏而实现的
Yuhan Liang1, Di Yi1, Tianxiang Nan2
1School of Materials Science and Engineering, Tsinghua University, Beijing, China.
Nature communications
|September 6, 2023
概括
研究人员在Pt/Co异构结构中实现了无场旋转轨道扭矩 (SOT) 切换,通过工程突移Burgers向量. 这种方法打破了平面对称性,使磁性存储器在室温下能够高效稳定地工作.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 这就是Spintronics.
背景情况:
- 电流诱导的旋转轨道扭矩 (SOT) 对先进的磁性内存至关重要.
- 无场SOT切换需要打破内平面对称性,通常通过外部场或设备不对称性实现.
- 利用固有的晶体对称性为SOT材料的无场切换提供了一个有希望但具有挑战性的途径.
研究的目的:
- 开发一种新的策略,用于打破Pt/Co异构结构中的平面对称性,以实现无场SOT切换.
- 为了研究工程脱位汉堡向量对磁性特性的影响.
- 为了证明在室温下高效和稳定的无现场SOT切换.
主要方法:
- 设计具有特定位移 Burgers 矢量方向的 Pt/Co 异构结构.
- 使用X射线衍射证实格子倾斜和特征结构修改.
- 在不同电流密度下测量SOT切换效率和稳定性.
主要成果:
- 在 Pt/Co 中,由平面外的 Burgers 矢量诱导了 ~1.2° 的格子倾斜.
- 这种倾斜导致了一个可调节的,倾斜的磁性轻松轴,从内平面到外平面.
- 在室温下实现了垂直磁化的无场SOT切换,电流密度低 (~10^11 A/m^2),稳定性高 (>10^4周期).
结论:
- 工程位移Burgers向量是一种有效的方法来打破对称性并实现无场SOT切换.
- 这种方法为开发下一代磁性存储器设备提供了可行的途径.
- 该策略广泛适用于各种电子和磁性设备中的与对称性相关的工程功能.
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