Spin diffusion of a two-dimensional electron gas in the random phase approximation

Spin transport properties of spin-polarized two-dimensional electron gas are studied in the presence of electron–electron interactions. Longitudinal and transverse spin diffusion coefficients are calculated with the quantum transport equation. New results are obtained by evaluating both the drift and the collision terms using the random phase approximation, while the drift term was calculated by Hartree–Fock approximation in our earlier work. The qualitative features remain same, but the present work is valid for larger polarizations. We find that the e–e scattering, which does not contribute to the charge drift mobility, has a significant contribution to the spin diffusion.