Effect of interface structure on current spin-polarization in narrow gap semiconductor heterostructures

We investigate numerically the effect of the interface structure on the spin-polarization of the electron transmission through zinc-blend semiconductor double barrier resonant tunneling heterostructures in which the well and barrier have a different composition of both anions and cations. Based on the atomistic sp3s* tight binding model calculations including the intra-atomic spin–orbit interaction, it is demonstrated that the asymmetric configuration of the two barrier/well interfaces results in the strongly anisotropic spin-splitting of the transmission without use of the external electric field, where the interface asymmetry is interpreted to cause the additional effective spin–orbit coupling analogous to the Rashba spin–orbit coupling mechanism.