从周边金属-抗铁磁绝缘体接口产生皮秒旋转电流
1National Laboratory of Solid State Microstructures, Jiangsu Provincial Key Laboratory for Nanotechnology, Collaborative Innovation Center of Advanced Microstructures and Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
Physical review letters
|May 10, 2024
概括
我们在室温下使用激光脉冲在附近的反铁磁绝缘体接口上演示了皮秒旋转电流的产生. 这种自旋电流,转换为太赫兹辐射,起源于界面对称性破坏,为超快速自旋电子学开辟了新的途径.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 这就是Spintronics.
- 材料科学 材料科学 材料科学
背景情况:
- 抗铁磁材料由于其快速动力学和强度,为先进的自旋电子设备提供了潜力.
- 超高速旋转电流的产生对于高速信息处理至关重要.
- 接口工程是控制异构结构中旋转动态的关键.
研究的目的:
- 为了研究在重金属和附近的反铁磁绝缘体 (Cr2O3) 之间的接口上,皮秒旋转电流的产生.
- 探索界面对称性破坏在产生和检测自旋电流中的作用.
- 建立邻近接口和超快旋转动态之间的联系.
主要方法:
- 使用激光脉冲在室温和零磁场下激发重金属/Cr2O3接口.
- 检测重金属中通过反旋转霍尔效应产生的太赫兹辐射.
- 改变Cr2O3表面的邻近角度,以研究其对旋转电流产生的影响.
主要成果:
- 在重金属/邻近反铁磁绝缘体接口上成功生成了皮秒旋转电流.
- 观察到的太赫兹信号与周边角直接成比例,证实了它的作用.
- 将旋转电流的起源归因于界面非线性磁双极差的频率产生.
- 提出了一个基于平面内反向对称性破坏的模型来解释观察到的太赫兹强度.
结论:
- 抗铁磁绝缘体中的旁边接口是超高速旋转电流生成的可行来源.
- 界面对称性破坏是产生短暂磁时和自旋电流的关键机制.
- 这项研究为开发新型反铁磁和超高速自旋电子设备提供了新的途径.
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