对于旋转轨道扭矩切换的对称性破坏效应在铁磁半导体中具有垂直磁性异构的磁性半导体
Apu Kumar Jana1, Sanghoon Lee2
1Physics Department, Korea University, Seoul, 136-701, Republic of Korea.
Scientific reports
|July 7, 2025
概括
对称性破坏可以在铁磁半导体中实现无场旋转轨道扭矩 (SOT) 切换. 各种内在和外在因素影响切换行为,对旋转电子技术的进步至关重要.
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:
- 具有垂直磁性异构 (PMA) 的铁磁半导体 (FMS) 是先进的自旋电子设备的关键.
- 旋转轨道扭矩 (SOT) 切换提供了高效的磁化操纵.
- 了解对称性破坏效应对于优化SOT切换至关重要.
研究的目的:
- 研究在FMS与PMA中SOT切换的机制,重点是对称性破坏.
- 分析各种对称性破坏因素对SOT切换行为的影响.
- 探索实现无现场SOT (FF-SOT) 切换的新方法.
主要方法:
- 使用兰道-利夫希茨-吉尔伯特 (LLG) 方程进行微磁模拟.
- 对称性破坏因素的检查:偏差场不对齐,层间交换合,外平面旋转极化和倾斜的磁性异构.
- 欧斯特德场诱导的对称性破坏的分析.
主要成果:
- 偏差场的错位扭曲了SOT切换的歇斯底里.
- 内在的破坏对称性因素使FF-SOT可以在没有外部偏差的情况下切换.
- 层间交换偏差和倾斜的异形性相结合的影响显著改变开关电流密度.
- 奥斯特德场在特定的晶体学方向上提供了一种新的对称性破坏方法.
结论:
- 对称性破坏在FMS中实现FF-SOT切换方面发挥着关键作用.
- 不同的FF-SOT切换机制观察到不同的特征.
- 这项研究为解释FMS中的FF-SOT切换实验结果提供了基本的见解.
- 这些发现有助于优化SOT的效率和推进自旋电子技术.
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