1] Center for Spintronics, Korea Institute of Science and Technology, Seoul 136-791, Korea [2] KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701, Korea.
Center for Spintronics, Korea Institute of Science and Technology, Seoul 136-791, Korea.
Nat Nanotechnol. 2015 Aug;10(8):666-70. doi: 10.1038/nnano.2015.107. Epub 2015 May 25.
The spin-orbit interaction in two-dimensional electron systems provides an exceptionally rich area of research. Coherent spin precession in a Rashba effective magnetic field in the channel of a spin field-effect transistor and the spin Hall effect are the two most compelling topics in this area. Here, we combine these effects to provide a direct demonstration of the ballistic intrinsic spin Hall effect and to demonstrate a technique for an all-electric measurement of the Datta-Das conductance oscillation, that is, the oscillation in the source-drain conductance due to spin precession. Our hybrid device has a ferromagnet electrode as a spin injector and a spin Hall detector. Results from multiple devices with different channel lengths map out two full wavelengths of the Datta-Das oscillation. We also use the original Datta-Das technique with a single device of fixed length and measure the channel conductance as the gate voltage is varied. Our experiments show that the ballistic spin Hall effect can be used for efficient injection or detection of spin polarized electrons, thereby enabling the development of an integrated spin transistor.
二维电子系统中的自旋轨道相互作用提供了一个极其丰富的研究领域。在自旋场效应晶体管的通道中，在拉什巴有效磁场中相干的自旋进动和自旋霍尔效应是这一领域中最引人注目的两个主题。在这里，我们将这些效应结合起来，直接证明了弹道本征自旋霍尔效应，并展示了一种用于全电测量达塔-达斯电导振荡的技术，即由于自旋进动导致源漏电导的振荡。我们的混合器件有一个铁磁电极作为自旋注入器和自旋霍尔探测器。具有不同沟道长度的多个器件的结果描绘出了达塔-达斯振荡的两个完整波长。我们还使用原始的达塔-达斯技术，用一个固定长度的单一器件测量沟道电导随栅极电压的变化。我们的实验表明，弹道自旋霍尔效应可用于高效注入或探测自旋极化电子，从而实现集成自旋晶体管的发展。
