Scattering induced spin orientation and spin currents in gyrotropic structures

It is shown that additional contributions both to current-induced spin orientation and to the spin Hall effect arise in quantum wells due to gyrotropy of the structures. Microscopically, they are related to basic properties of gyrotropic systems, namely, linear in the wave vector terms in the matrix element of electron scattering and in the energy spectrum. Calculation shows that in high-mobility structures the contribution to the spin Hall current considered here can exceed the term originated from the Mott skew scattering.