  The influence of inelastic relaxation time on the intrinsic spin Hall effects
in a disordered two-dimensional electron gas with Rashba interaction is
studied, which clarifies the controversy of impurity effects in the system. We
reveal that, due to the existence of inelastic scattering, the spin Hall
conductivity does not vanish when the impurity concentration diminishes to zero
no matter it is non-magnetically or magnetically disordered. The spin
accumulation is evaluated by using the obtained spin Hall conductivity, and an
alternate route is suggested to verify the intrinsic spin Hall effect by
measuring the spin accumulation at different ratios.
