Spin-dependent electron transport in nonmagnetic semiconductor nanostructures

In this paper we investigate the effects of spin-orbit coupling mechanisms on electronic transport in multilayer semiconductor structures and explore their prospective applications to spin-manipulation devices. A model is presented for estimating the influence of combined Rashba spin-orbit interactions, induced by the structural asymmetry, and Dresselhaus spin-orbit coupling, caused by the bulk inversion asymmetry, on the spin-polarization status of the tunneling electrons. The proposed structures are expected to enable spin separation without exploiting the magnetic properties of constituent materials, and should therefore be realizable by conventional nonmagnetic semiconductors only, The degree of spin-polarization may eventually be enhanced by careful tailoring of the structural parameters. (c) 2007 Elsevier B.V. All rights reserved.