Electrical generation of spin in crystals with reduced symmetry

We propose a way of generating a spin polarization in crystals with strong spin-orbit interactions. We show that, in the presence of an electric field, there exists an intrinsic torque term which gives rise to a nonzero spin generation rate. This spin generation rate is experimentally observable, as recent experimental progress in the detection of spin accumulation has shown. The wide applicability of this effect is emphasized by explicit consideration of a range of examples: bulk wurtzite and strained zincblende ($n$-GaAs) lattices, as well as quantum well heterojunction systems.