Efficient spin injection and spin filtering in semiconductors by utilizing the k3-Dresselhaus spin-orbit effect

Abstract

We numerically study the spin-dependent transmission characteristic of conduction electrons across a semiconductor-based trilayer structure with k 3-Dresselhaus spin-orbit coupling, where the Fermi level of electrons exceeds the electrostatic barrier height. Unlike previous studies which focus on the tunneling regime, the electron transmission across our structure is high, thereby ensuring that the polarization can be utilized in a practical device. The polarization is studied for two barrier materials, GaSb and InSb, which both show a considerable polarization amplitude attainable within realistic modeling values. We finally propose two interesting spintronic device concepts based on our structure and its unique polarization characteristics; a sensitive, gate-tunable spin filter and a novel spin transistor device. © 2008 IEEE.