Magnetic polarization of the tunneling current

In this work, we theoretically study the spin-dependent transport in a magnetic tunnel junction (MTJ). Using a simple model and ballistic transport, the magnetic polarization of the tunneling current on this system is studied by focusing on the tunneling of s and d electrons. We investigate the tunneling of these electrons through potential barriers, which represents the insulating layer between the ferromagnetic electrodes. We also examine how the conductance depends on voltage applied between the electrodes and on the effective mass of the electrons. The conductance is controlled by the transmission coefficient of the tunnel effect, and qualitatively it is known that tunneling probability of the d electrons is lower than the s electrons. We also estimate the effect of the tunneling magnetoresistance (TMR) and it is strongly influenced by the effective mass of the electrons. The s electrons do not contribute significantly to the TMR.