Drift and diffusion of spins generated by the spin Hall effect

Electrically generated spin accumulation due to the spin Hall effect is imaged in n-GaAs channels using Kerr rotation microscopy, focusing on its spatial distribution and time-averaged behavior in a magnetic field. Spatially resolved imaging reveals that spin accumulation observed in transverse arms develops due to the longitudinal drift of spin polarization produced at the sample boundaries. One- and two-dimensional drift-diffusion modeling is used to explain these features, providing a more complete understanding of observations of spin accumulation and the spin Hall effect.