Institute for Solid State Physics, University of Tokyo, Kashiwa, Japan.
Sci Rep. 2012;2:628. doi: 10.1038/srep00628. Epub 2012 Sep 4.
Non-local spin injection in lateral spin valves generates a pure spin current which is a diffusive flow of spins (i.e. spin angular momentums) with no net charge flow. The diffusive spins lose phase coherency in precession while undergoing frequent collisions and these events lead to a broad distribution of the dwell time in a transport channel between the injector and the detector. Here we show the lateral spin-valves with dual injectors enable us to detect a genuine in-plane precession signal from the Hanle effect, demonstrating the phase coherency in the in-plane precession is improved with an increase of the channel length. The coherency in the spin precession shows a universal behavior as a function of the normalized separation between the injector and the detector in material-independent fashion for metals and semiconductors including graphene.
横向自旋阀中的非局域自旋注入产生纯自旋流，它是自旋（即自旋角动量）的扩散流，没有净电荷流。扩散的自旋在进动过程中由于频繁的碰撞而失去相位相干性，这些事件导致在注入器和探测器之间的输运通道中的停留时间分布很宽。在这里，我们展示了具有双注入器的横向自旋阀能够使我们从 Hanle 效应中检测到真正的面内进动信号，证明了随着通道长度的增加，面内进动的相位相干性得到了提高。自旋进动的相干性表现出一种普遍的行为，作为注入器和探测器之间的归一化分离的函数，对于包括石墨烯在内的金属和半导体等材料是独立的。
