Simulation of Spin-Dependent Electronic Transport through Resonant Tunnelling Diode with Paramagnetic Quantum Well

The spin-dependent electronic transport is investigated in a paramagnetic resonant tunnelling diode formed from Zn$\text{}_{1 - x}$Mn$\text{}_{x}$Se quantum well between two ZnBeSe barrier layers. The spin-dependent current-voltage characteristics have been obtained in the presence of magnetic fields by solving the quantum kinetic equation for the Wigner distribution function and the Poisson equation in the self-consistent procedure. We have obtained two distinct current peaks due to the giant Zeeman splitting of electronic levels in a qualitative agreement with experiment. We have shown that the sign of spin current polarization can be reversed by tuning the bias voltage. Moreover, we have found the bias voltage windows with a nearly constant polarization.