Pure spin-current diode based on interacting quantum dot tunneling junction  

作　　者：Zhengzhong Zhang Min Yu Rui Bo Chao Wang Hao Liu 张正中;余敏;薄锐;王超;刘昊(Faculty of Mathematics and Physics,Huaiyin Institute of Technology,Huaian 223003,China;The Affiliated Drum Tower Hospital of Nanjing University Medical School,Nanjing 210093,China)

机构地区：[1]Faculty of Mathematics and Physics,Huaiyin Institute of Technology,Huaian 223003,China [2]The Affiliated Drum Tower Hospital of Nanjing University Medical School,Nanjing 210093,China

出　　处：《Chinese Physics B》2021年第11期545-550,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.11404322);the Natural Science Foundation of Huai’an(Grant No.HAB202150).

摘　　要：A magnetic field-controlled spin-current diode is theoretically proposed,which consists of a junction with an interacting quantum dot sandwiched between a pair of nonmagnetic electrodes.By applying a spin bias VS across the junction,a pure spin current can be obtained in a certain gate voltage regime,regardless of whether the Coulomb repulsion energy exists.More interestingly,if we applied an external magnetic field on the quantum dot,we observed a clear asymmetry in the spectrum of spin current IS as a function of spin bias,while the charge current always decays to zero in the Coulomb blockade regime.Such asymmetry in the current profile suggests a spin diode-like behavior with respect to the spin bias,while the net charge through the device is almost zero.Different from the traditional charge current diode,this design can change the polarity direction and rectifying ability by adjusting the external magnetic field,which is very convenient.This device scheme can be compatible with current technologies and has potential applications in spintronics or quantum processing.

关 键 词：pure spin current semiconductor quantum dot spin diode 

分 类 号：O469[理学—凝聚态物理]