The electron transport through a Rashba ring with a magnetic flux and driven by a temperature difference is investigated. It is found that the spin interference effect induced by the Rashba spin-orbit interaction and ...The electron transport through a Rashba ring with a magnetic flux and driven by a temperature difference is investigated. It is found that the spin interference effect induced by the Rashba spin-orbit interaction and by the magnetic flux can break the balance between the spin-up and spin-down component currents in the thermally driven charge current and thus result in a spin current. The analytical derivation and numerical calculations reveal that the magnitude, sign, peaks and spin-polarization of the generated spin current can be readily modulated by the system parameters. In particular, with some choices of the parameters, the spin polarization of the generated spin current can reach 100%, that is, a fully spin-polarized thermospin current can be produced. These results may help the use of the spin-dependent Seebeck effect to generate and manipulate a spin current.展开更多
We theoretically predict the appearance of a persistent charge current in a Rashba ring with a normal and a ferromagnetic lead under no external bias. This charge current is the result of the breaking of the time inve...We theoretically predict the appearance of a persistent charge current in a Rashba ring with a normal and a ferromagnetic lead under no external bias. This charge current is the result of the breaking of the time inversion symmetry in the original persistent pure spin current induced by the Rashba spin-orbit coupling （RSOC） in the ring due to the existence of the ferromagnetic lead. With the Keldysh Green＇s function technique, we find that not only the magnitude and sign but also the spin polarization of＇the generated charge current is determined by the system parameters such as the magnetization direction of the ferromagnetic lead, the tunneling coefficient, the strength of the RSOC and the exchange energy of the ferromagnetic lead, which are all tunable in experiments, that is, a controllable persistent spin-polarized charge current can be obtained in such a device.展开更多
基金Project supported by the National Natural Science Foundation of China (No.11404142)
文摘The electron transport through a Rashba ring with a magnetic flux and driven by a temperature difference is investigated. It is found that the spin interference effect induced by the Rashba spin-orbit interaction and by the magnetic flux can break the balance between the spin-up and spin-down component currents in the thermally driven charge current and thus result in a spin current. The analytical derivation and numerical calculations reveal that the magnitude, sign, peaks and spin-polarization of the generated spin current can be readily modulated by the system parameters. In particular, with some choices of the parameters, the spin polarization of the generated spin current can reach 100%, that is, a fully spin-polarized thermospin current can be produced. These results may help the use of the spin-dependent Seebeck effect to generate and manipulate a spin current.
文摘We theoretically predict the appearance of a persistent charge current in a Rashba ring with a normal and a ferromagnetic lead under no external bias. This charge current is the result of the breaking of the time inversion symmetry in the original persistent pure spin current induced by the Rashba spin-orbit coupling （RSOC） in the ring due to the existence of the ferromagnetic lead. With the Keldysh Green＇s function technique, we find that not only the magnitude and sign but also the spin polarization of＇the generated charge current is determined by the system parameters such as the magnetization direction of the ferromagnetic lead, the tunneling coefficient, the strength of the RSOC and the exchange energy of the ferromagnetic lead, which are all tunable in experiments, that is, a controllable persistent spin-polarized charge current can be obtained in such a device.
