Conductance in an Aharonov-Bohm Interferometer with Parallel-Coupled Double Dots  

作　　者：安兴涛 赵金荣 刘建军 

机构地区：[1]College of Physical Science and Information Engineering, Hebei Normal University, Shijiazhuang, Hebei 050016 [2]Hebei Advanced Thin Films Laboratory, Shijiazhuang, Hebei 050016 [3]First Middle School of Zhangjiakou, Zhangjiakou, Hebei 075000

出　　处：《Chinese Physics Letters》2009年第9期223-226,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No 10674040, and the Specialized ReSearch Fund for the Doctoral Program of Higher Education of China under Grant No 20060094002.

摘　　要：We present a theoretical study of the conductance in an Aharonov-Bohm interferometer containing two coupled quantum dots. The interdot tunneling divides the interferometer into two coupled subrings, where opposite magnetic fluxes are threaded separately while the net flux is kept zero. Using the Green function technique we derive the expression of the linear conductance. It is found that the Aharonov-Bohm effect still exists, and when the level of each dot is aligned, the exchange of the Fano and Breit-Wigner resonances in the conductance can be achieved by tuning the magnetic flux. When the two levels are mismatched the exchange may not happen. Further, for some specific asymmetric systems where the coupling strengths between the two dots and the leads are not equal, the flux can change the Fano resonance into an antiresonance, which is absent in symmetric systems.We present a theoretical study of the conductance in an Aharonov-Bohm interferometer containing two coupled quantum dots. The interdot tunneling divides the interferometer into two coupled subrings, where opposite magnetic fluxes are threaded separately while the net flux is kept zero. Using the Green function technique we derive the expression of the linear conductance. It is found that the Aharonov-Bohm effect still exists, and when the level of each dot is aligned, the exchange of the Fano and Breit-Wigner resonances in the conductance can be achieved by tuning the magnetic flux. When the two levels are mismatched the exchange may not happen. Further, for some specific asymmetric systems where the coupling strengths between the two dots and the leads are not equal, the flux can change the Fano resonance into an antiresonance, which is absent in symmetric systems.

分 类 号：TN304.21[电子电信—物理电子学] TH744.3[机械工程—光学工程]