平行耦合双量子点分子A-B干涉仪的电荷及其自旋输运  

Charge and spin transport through parallel-coupled double-quantum-dot molecule A-B interferometer

作　　者：白继元[1] 贺泽龙[1] 杨守斌[2] 

机构地区：[1]黑龙江工程学院电气与信息工程学院,哈尔滨150050 [2]哈尔滨师范大学,哈尔滨150025

出　　处：《物理学报》2014年第1期319-326,共8页Acta Physica Sinica

基　　金：黑龙江省教育厅科学技术研究项目(批准号:12531543)资助的课题~~

摘　　要：利用非平衡格林函数方法,理论研究每臂中嵌有一个平行耦合双量子点分子的A-B干涉仪(平行耦合双量子点分子A-B干涉仪)的电荷及其自旋输运性质.无外磁场时,与每臂中嵌有一个量子点的A-B干涉仪相比较,平行耦合双量子点分子A-B干涉仪中电子隧穿变得更加容易发生.当平行耦合双量子点分子A-B干涉仪中引入外磁场时,能够在电导能谱中观察到一个Fano共振和一个反共振,这两种输运状态在磁场取适当数值时能够同时消失.此外,通过调节左右两电极间的偏压、磁通和Rashba自旋轨道相互作用,可以对体系自旋输运进行调控.By using the nonequilibrium Green＇s function technique,the charge and spin transport properties through an A-B interferometer that has a parallel-coupled double-quantum-dot molecule embedded in each arm,（named as parallelcoupled double-quantum-dot molecule A-B interferometer） are investigated.In the absence of magnetic fux,as compared with the A-B interferometer with two quantum dots embedded in each arm,electron tunnelling becomes far easier for parallel-coupled double-quantum-dot molecule A-B interferometer.When the magnetic feld is introduced,one can observe in the conductance spectrum one Fano resonance and one anti-resonance,both of which will die away simultaneously when the magnetic fux takes a proper value.Besides,spin transport can be manipulated by tuning the bias voltage between the two leads,magnetic fux,and Rashba spin orbit interaction.

关 键 词：非平衡格林函数 量子点 A-B干涉仪 自旋输运 

分 类 号：O431.2[机械工程—光学工程]