By means of the Keldysh Green's function method,we investigate the spin-polarized electron transport in a three-terminal device,which is composed of three normal metal leads and two serially-coupled quantum dots(Q...By means of the Keldysh Green's function method,we investigate the spin-polarized electron transport in a three-terminal device,which is composed of three normal metal leads and two serially-coupled quantum dots(QDs).The Rashba spin-orbit interaction(RSOI) is also considered in one of the QDs.We show that the spin-polarized charge current with arbitrary spin polarization can be obtained because of the quantum spin interference effect arising from the Rashba spin precession phase,and it can be modulated by the system parameters such as the applied external voltages,the RSOI strength,the QD levels,as well as the dot-lead coupling strengths.Moreover,a fully spin-polarized current or a pure spin current without any accompanying charge current can also be controlled to flow in the system.Our findings indicate that the proposed model can serve as an all-electrical spin device in spintronics field.展开更多
基金Supported by National Natural Science Foundation of China under Grant Nos. 10704016,110704032,110704033Natural Science Foundation of Jiangsu Province under Grant No. BK2010416National Basic Research Project of China under Grant No. 2009CB945504
文摘By means of the Keldysh Green's function method,we investigate the spin-polarized electron transport in a three-terminal device,which is composed of three normal metal leads and two serially-coupled quantum dots(QDs).The Rashba spin-orbit interaction(RSOI) is also considered in one of the QDs.We show that the spin-polarized charge current with arbitrary spin polarization can be obtained because of the quantum spin interference effect arising from the Rashba spin precession phase,and it can be modulated by the system parameters such as the applied external voltages,the RSOI strength,the QD levels,as well as the dot-lead coupling strengths.Moreover,a fully spin-polarized current or a pure spin current without any accompanying charge current can also be controlled to flow in the system.Our findings indicate that the proposed model can serve as an all-electrical spin device in spintronics field.
