Lateral shifts of spin electron beams in antiparallel double δ-magnetic-barrier nanostructure

We investigate the Goos-Hanchen (GH) effect of spin electron beams in a magnetic-barrier (MB) nanostructure consisting of antiparallel double delta-MBs, which can be experimentally realized by depositing two ferromagnetic (FM) stripes on top and bottom of the semiconductor heterostructure. GH shifts for spin electron beams across this type of MB nanostructures, is derived exactly, with the help of the stationary phase method. It is shown that GH shifts depend strongly on the spin directions for double delta-MBs with unidentical magnetic strengths, giving rise to a considerable spin polarization effect. It also is shown that spin polarization of GH shifts is closely relative to the separation and magnetic-strength difference of two delta-MBs. These interesting properties may provide an alternative scheme to spin-polarize electrons into the semiconductor, and the devices can serve as tunable spin beam splitters. (C) 2012 Elsevier By. All rights reserved.