Study of couplings effect on the performance of a spin-current diode:   Nonequilibrium Green's function based model
  In this paper, spin-dependent transport through a spin diode composed of a quantum dot coupled to a normal metal and a ferromagnetic lead is studied. The current polarization and the spin accumulation are analyzed using the equations of motion method within the nonequilibrium Green's function formalism. We present a suitable method for computing Green's function without carrying out any self-consistent calculation. The influence of coupling strength and magnetic field on the spin current is studied and observed that this device cannot work as a spin diode under certain conditions. 
M. Bagheri Tagani, H. Rahimpour Soleimani
cond-mat.mes-hall