Spin filtering in magnetic/semiconductor hybrid nanostructures

We study theoretically the spin-dependent electron transport in realistic magnetic-barrier nanostructures, which can be experimentally realized by depositing a magnetized ferromagnetic stripe with arbitrary magnetization direction on the surface of a semiconductor heterostructure. It is shown that highly spin-polarized current can be achieved in this kind of nanostructures. It is also shown that the spin polarity of the electron transport can be switched by adjusting the magnetized angle of the ferromagnetic stripe in the system. These interesting properties may provide an alternative scheme to spin-polarize electrons into semiconductors and may be used as a spin-filter. (c) 2005 Elsevier B.V. All rights reserved.