Electron spin filter based on Rashba spin-orbit coupling

The authors present an electron spin filter that consists of a branching structure under the influence of Rashba spin-orbit coupling. The magnitude of the spin polarization in this device can be tuned by the strength of the spin-orbit interaction. The authors find that the mechanism for the spin filtering is the spatial modulation of the spin-resolved wave functions due to the influence of the Rashba effect. The authors also find evidence suggesting that the geometry of the branch at the junction point is primarily responsible for the strength of the spin polarization.