Rashba spin-orbit effect on spin-tunneling time in a ferromagnetic/semiconductor/ferromagnetic heterojunction with a tunnel barrier.

The electronic transport properties are studied theoretically in a ferromagnetic/semiconductor/ferromagnetic heterojunction with a tunnel barrier. The Rashba spin-orbit interaction in the semiconductor and the significant quantum size are taken into account simultaneously. It is found that the tunnel barrier plays a decisive role in the transmission coefficients of spin-up and spin-down electrons. On the basis of the group velocity concept and the particle current conservation principle, the spin-tunneling time is obtained as a function of the intensity of the Rashba spin-orbit coupling and the length of the semiconductor, respectively. It is shown that as the length of the semiconductor increases, the behavior of the spin-tunneling time oscillates slightly. Both the Rashba spin-orbit coupling and the tunnel barrier damps the motion of electrons, and so the tunneling time of electrons is increased. [ABSTRACT FROM AUTHOR]