Deterministic transfer of spin polarization in wire-like lateral structures via the persistent spin helix

We used spatiallyand time-resolved Kerr rotation microscopy to show that in lateral wire-like structures, based on a modulation-doped GaAs-AlGaAs quantum well, an optically initialized spin polarization can be deterministically transferred to specific lateral positions, employing the persistent spin helix (PSH). To this end, we show that confinement in two directions leads to a strong enhancement of the effective decay time of spin polarization, which can be exploited to transfer spin polarization over relatively large lateral distances. This is demonstrated by the investigation of L-shaped wire-like lateral structures, where the legs are positioned in directions parallel and perpendicular to the wave vector of the PSH. Published by AIP Publishing. [http://dx.doi.org/10.1063/1.4966184]