Spin-orbit coupling and spin transport

Recent achievements in semiconductor spintronics are discussed. Special attention is paid to spin-orbit interaction, coupling of electron spins to external electric fields, and spin transport in media with spin-orbit coupling, including the mechanisms of spin-Hall effect. Importance of spin-transport parameters at spin-precession wave vector k(so) is emphasized, and existence of an universal relation between spin currents and spin accumulation at the spatial scale of l(so) approximate to k(so)(-1) is conjectured. (c) 2006 Elsevier B.V. All rights reserved.