Controllable spin beam splitter by δ-doping in antiparallel double δ-magnetic-barrier nanostructure

For an antiparallel double δ-magnetic-barrier nanostructure, there is no spin polarization due to the intrinsic symmetry. When a δ-doping is included, it is theoretically demonstrated that this device possesses a considerable spin polarization effect attributable to spin-dependent Goos-Hänchen (GH) effect of electrons. Moreover, numerical calculations show that both magnitude and sign of spin polarization in GH shifts are closely relative to height and/or location of the δ-doping, which can give rise to a controllable spin beam splitter.