Co-ordination between the Rashba spin orbital interaction and space charge effect and enhanced spin injection into semiconductors in the diffusion region

We consider the effect of the Rashba spin-orbital interaction and space charge in a ferromagnet-insulator/semiconductor/insulator-ferromagnet junction where the spin current is severely affected by the doping, band structure and charge screening in the semiconductor. In the diffusion region, if the resistance of the tunnelling barriers is comparable to the semiconductor resistance, the magnetoresistance of this junction can be greatly enhanced under appropriate doping by the co-ordination between the Rashba effect and the screened Coulomb interaction in non-equilibrium transport processes within the Hartree approximation.