Intrinsic oscillation of spin accumulation induced by Rashba spin-orbital interaction

The Green's function approach is applied to studying the nonequilibrium spin accumulation in real space induced by the Rashba spin-orbital interaction (RSOI) in a quantum wire device. Both the leads and sample are assumed to have the same RSOI to exclude spin-dependent scattering at interfaces between them. It is found that the spin accumulation concentrates antisymmetrically on two lateral edges of the sample and exhibits an intrinsic Rashba spin precession along the current direction. This oscillation of spin accumulation can be used in experimental observations to differentiate the intrinsic spin accumulation from the extrinsic one, the latter stemming from impurity scattering in the presence of spin-orbit interactions.