Spin polarization in multilayer ferromagnetic semiconductor

We focus on transport of electron spins, which spin-polarized currents can be controlled and manipulated via the electron energy and momentum. We study in this paper the electronic properties of ferromagnetic phase of a multilayer ferromagnetic semiconductor in the mean-field and effective mass approximations, as a result of the magnetic interaction between holes and Mn ions, the magnetic layers acts as potential barriers for holes with spin-up, and as potential wells for the inverse spin polarization. As an example we calculate the dependence of hole density and the spin polarization in terms of the band offset vw which describes the difference in electronegativity between the Mn and GaAs atoms. Our calculations are performed using a self-consistent procedure to solve Schrödinguer and Poisson equations taking into account the coulomb interaction between holes.