Spin-polarized transport in a lateral two-dimensional diluted magnetic semiconductor electron gas

The transport property of a lateral two-dimensional diluted magnetic semiconductor electron gas under a spatially periodic magnetic field is investigated theoretically. We find that the electron Fermi velocity along the modulation direction is highly spin-dependent even if the spin polarization of the carrier population is negligibly small. It turns out that this spin-polarized Fermi velocity alone can lead to a strong spin polarization of the current, which is still robust against the energy broadening effect induced by the impurity scattering.