Spin-orbit coupling and the electronic properties of quantum wires

Abstract

We review recent work on the effects of the Rashba spin-orbit interaction on the electronic structure and the conductance of quantum wires. We first discuss the importance of the intersubband coupling induced by the Rashba interaction for the wire subband-energies and spin distributions, especially in the presence of in-plane magnetic fields. We then consider the calculation of the evanescent modes, emphasizing the peculiarities of these states in the presence of spin-orbit coupling. Finally, we discuss the physical effects of a localized Rashba interaction in a quantum wire. We predict in this case the occurrence of Fano resonances in the dependence of the wire conductance with the incident electron energy. The Fano lineshapes manifest themselves more clearly in the spin-resolved transmissions. We obtain exact numerical results within the quantum-transmittingboundary algorithm and also propose a simplified approach (the coupled-channel model) that captures the main ingredients of the effect and allows a more transparent physical interpretation.