Bias current effects on the magnetoresistance of a ferromagnetic-semiconductor-ferromagnetic trilayer

The authors apply a self-consistent ballistic-diffusive theoretical model to study the bias current j effect on the magnetoresistance of a ferromagnet (FM)-semiconductor (SC)-FM trilayer, with SC highly doped (n(++)). The interfacial resistance becomes a dynamic parameter and its decrease with increasing j would be responsible for the decrease of magnetoresistance (MR) with j. The underlying physics of this model is based on a self-consistent treatment between the spin drift diffusion transport of electrons in the bulk and ballistic transmission at the interfaces. This model applies qualitatively to the more common FM-nonmagnetic-FM, metal-based current-perpendicular-to-plane spin valve, which has shown experimentally observed decline of MR with j. (c) 2007 American Institute of Physics.