三终端量子点环中的自旋极化输运

利用非平衡态格林函数方法,研究了一个存在局域Rashba自旋轨道耦合作用的三电极量子点环结构中的电子输运性质.结果发现,Rashba自旋轨道耦合作用引起的自旋相关的量子干涉效应能够在电极中产生自旋流.这种自旋流的大小、方向以及自旋极化度等性质可以通过纯电学手段改变系统参数来加以调控.在适当选择这些参数时,电极中甚至可以产生完全自旋极化流或纯自旋流.这些效应说明我们所研究的系统可用来设计纯电学的自旋流产生装置.

Spin-polarized Transport in a Three-terminal Quantum Dot Ring

With nonequilibrium Green's function method,we investigate the electron transport properties in a three terminal quantum dot ring structure in the absence of local Rashba spin-orbit interaction.It is found that the spin interference effect induced by the Rashba spin-orbit interaction can cause a spin current to flow in the electrode.The properties of this spin current such as its magnitude、flowing direction and spin polarization can be modulated by adjusting system parameters electrically.As these parameters are chosen properly,a fully spin-polarized current or a pure spin current can be generated in the electrode.Such effects suggest that the studied system may act as an all-electric generator of spin current.