时间域观测弹道轨道-角度-动量电流与巨大的放松长度在
Tom S Seifert1,2, Dongwook Go3,4, Hiroki Hayashi5,6
1Department of Physics, Freie Universität Berlin, Berlin, Germany. tom.seifert@fu-berlin.de.
Nature nanotechnology
|August 7, 2023
概括
研究人员观察到轨道材料中的超快电子轨道运动量传输. 这种势头可以在很远的距离上弹道地传播,从而使未来高密度,高速电子设备的潜在应用成为可能.
科学领域:
- 物理 物理学 物理
- 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
背景情况:
- 轨道电子利用电子轨道角动量 (L) 来进行磁性信息传输.
- 与旋转相比,轨道动量为更高密度和更长距离的信息传输提供了潜力.
- 对轨道角动量电流及其转化为电荷电流的实验观测仍然具有挑战性.
研究的目的:
- 为了光学触发和实验观察超快轨道角运动量传输.
- 为了研究轨道角动量电流的传播长度和速度.
- 为了研究轨道角动量转化为在接口上的电荷电流.
主要方法:
- 实验中利用了Ni gadWgadSiO2薄膜堆进行实验.
- 采用光学触发来启动超快的角运动量传输.
- 测量了太赫兹电荷电流爆发,并分析了它们对 (W) 厚度的依赖.
- 进行了初始计算以支持实验发现.
主要成果:
- 观测到的弹道轨道角运动量 (L) 从Ni到W的电流传输.
- 确定了大约80nm的巨型衰变长度和L电流的~0.1nm/fs的低速度.
- 在W/SiO2界面通过反轨道Rashba-Edelstein效应证明了L流的有效转换为电荷电流.
- 发现太赫兹电荷电流爆发显示延迟和宽度与W厚度线性增加.
结论:
- 轨道电子材料使得长距离弹道轨道轨道角动量传输成为可能.
- 这些发现为未来利用轨道角运动量的超高速设备铺平了道路.
- 该研究提供了一种方法来区分类似霍尔和Rashba-Edelstein的转换过程.
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