Spin Filter Based on an Aharonov-Bohm Interferometer with Rashba Spin-Orbit Effect

作     者：方明 孙连亮 

作者机构：Department of Physics and Institute of Graduate Students Bohai University Jinzhou 121000 College of Science North China University of Technology Beijing 100041 

出 版 物：《Chinese Physics Letters》 (中国物理快报（英文版）)

年 卷 期：2008年第25卷第9期

页      面：3389-3392页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 07[理学] 0809[工学-电子科学与技术（可授工学、理学学位）] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0704[理学-天文学] 0702[理学-物理学] 

主　　题：Spin Filter Aharonov--Bohm Interferometer Rashba Spin--Orbit Effect 

摘      要：We propose a spin filter based on both the quantum interference and the Rashba spin-orbit （RSO） effects. This spin filter consists of a Aharonov-Bohm （AB） interferometer with two quantum dots （QDs） inserted in its arms. The influences of a magnetic flux φ threading through the AB ring and the RSO interaction inside the two QDs are taken into account by using the nonequilibrium Green＇s function technique. Due to the existence of the RSO interaction, the electrons flowing through different arms of the ring will acquire a spin-dependent phase factor in the linewidth matrix elements. This phase factor, combined with the influence of the magnetic flux, will induce a spin-dependent electron transport through the device. Moreover, we show that by tuning the magnetic flux, the RSO strength and the inter-dot tunnelling coupling strength, a pure spin-up or spin-down conductance can be obtained when a spin-unpolarized current is injected from the external leads, which can be used to filter the electron spin.