Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Nat Commun. 2012 Jan 17;3:629. doi: 10.1038/ncomms1640.
The spin-orbit interaction in a solid couples the spin of an electron to its momentum. This coupling gives rise to mutual conversion between spin and charge currents: the direct and inverse spin Hall effects. The spin Hall effects have been observed in metals and semiconductors. However, the spin/charge conversion has not been realized in one of the most fundamental semiconductors, silicon, where accessing the spin Hall effects has been believed to be difficult because of its very weak spin-orbit interaction. Here we report observation of the inverse spin Hall effect in silicon at room temperature. The spin/charge current conversion efficiency, the spin Hall angle, is obtained as 0.0001 for a p-type silicon film. In spite of the small spin Hall angle, we found a clear electric voltage due to the inverse spin Hall effect in the p-Si film, demonstrating that silicon can be used as a spin-current detector.
在固体中，自旋-轨道相互作用将电子的自旋与其动量耦合在一起。这种耦合导致自旋和电荷电流之间的相互转换：直接和反自旋霍尔效应。自旋霍尔效应已在金属和半导体中观察到。然而，在最基本的半导体之一硅中，尚未实现自旋/电荷转换，因为其自旋-轨道相互作用非常弱，所以人们认为很难实现自旋霍尔效应。在这里，我们报告了在室温下硅中反自旋霍尔效应的观察结果。对于 p 型硅膜，获得的自旋/电荷电流转换效率（自旋霍尔角）为 0.0001。尽管自旋霍尔角很小，但我们在 p-Si 膜中发现了由于反自旋霍尔效应引起的明显电压，证明了硅可以用作自旋电流探测器。
