Spin-polarized currents in double quantum dots with Rashba spin-orbit interactions

We propose a new scheme of realizing spin-polarized currents in a double quantum dot system. In the presence of Rashba spin-orbit coupling interactions and different Zeeman splittings of each quantum dot, the currents are spin-polarized. The polarization can be controlled by tuning the strength of Rashba spin-orbit coupling and external magnetic fields, which can produce nearly 100% spin-polarized currents. Furthermore, we explain and analyze the mechanism of the strongly spin-polarized currents. Lastly we give two phase diagrams to display our results.