具有Stubs结构量子波导中电子的自旋传输特性

J4 ›› 2016, Vol. 33 ›› Issue (5): 628-634.

具有Stubs结构量子波导中电子的自旋传输特性

徐中辉¹,姜芸²,李艳玲¹,黄劲松¹,陈宇光³

1．江西理工大学信息工程学院,赣州 341000； 2．西安交通大学理学院,西安 710049； 3．同济大学物理科学与工程学院，上海 200092

收稿日期:2015-05-18 修回日期:2015-08-24 出版日期:2016-09-28 发布日期:2016-09-28
通讯作者: 徐中辉(1982-)，江西省赣县人，博士，讲师，从事低维纳米结构的研究。 E-mail:longxister@163.com
基金资助:
国家自然科学基金（11447118、11247032和11365011）；江西省教育厅科技项目（GJJ13383和GJJ13384）；江西省科技厅青年科学基金（20151BAB212004）；江西理工大学科研基金课题（NSFJ2014-G20）

Spin-dependent electron transport properties of quantum waveguide systems with attached stubs

XU Zhong-hui, JIANG yun, LI yan-ling, HUANG jin-song, CHEN yu-guang

1. Faculty of Information Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China; 2. Department of Applied Physics, Xi’an Jiaotong University, Xi’an 710049, China; 3. Department of Physics, Tongji University, Shanghai 200092, China

Received:2015-05-18 Revised:2015-08-24 Published:2016-09-28 Online:2016-09-28

摘要/Abstract

摘要： 利用递归格林函数法研究了含Rashba自旋轨道耦合效应的具有Stubs结构的量子波导中电子的自旋极化传输特性.结果表明在含一个stub的量子波导系统中, 由于stub和Rashba自旋轨道耦合引起的势阱导致系统电导出现Fano共振形式的“山谷”和“针尖”结构, 通过改变自旋轨道耦合的强度可以调节它们的大小. 同时,在同样的位置自旋极化率也出现Fano共振或反共振结构. 当系统中出现多个周期性的stubs时, 在Fano共振点附近电导中出现一些小的带隙结构.但是,当系统加上磁场后, stubs和自旋轨道耦合带来的效应都被抑制, 系统的电导重新出现量子化台阶结构. 同时由于子带间干涉效应变小, 自旋电导也出现台阶结构.

关键词: 量子物理；自旋传输特性；递归格林函数法；Stubs量子波导

Abstract: The spin-dependent electron transport properties of quantum waveguide systems with attached stubs in the presence of Rashba spin-orbit coupling (SOC) by the Recursive Green function (RGF) method are theoretically studied. In the single-stub Rashba SOC quantum waveguide system, the dip-like structure and valley-like structure emerge in the charge conductance spectra due to the stub-induced Potential well and SOC-induced Potential well. In addition，the peaks of the dip-like and valley-like structure can be controlled by changing the strength of Rashba SOC. At the same time, a series of resonant peaks and dips occur in the charge conductance and spin conductance, at the energies that correspond to the quasi-bound states in the stubs. Moreover, due to the presence of multiple modes and the mode-mixing effect as the number of stubs increases, there are some mini-bands exist in the charge conductance and spin polarization. However, the quantization plateau is gradually recovered, a set of resonances occurs in the charge conductance and spin conductance at the threshold of every transmitted mode when the system in the presence of an electromagnetic field.

Key words: Quantum physics; Spin-dependent electron transport properties; The Recursive Green function (RGF) method; Stubs quantum waveguide

中图分类号:

O471

徐中辉姜芸李艳玲黄劲松陈宇光. 具有Stubs结构量子波导中电子的自旋传输特性[J]. J4, 2016, 33(5): 628-634.

XU Zhong-hui, JIANG yun, LI yan-ling, HUANG jin-song, CHEN yu-guang. Spin-dependent electron transport properties of quantum waveguide systems with attached stubs[J]. J4, 2016, 33(5): 628-634.

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