Nonvanishing spin Hall conductivity in two-dimensional Rashba electron systems with nonparabolic Kane dispersion

We investigate the spin Hall effect in a two-dimensional (2D) Rashba spin-orbit coupled electron gas with nonparabolic Kane energy dispersion using the Green's function approach under self-consistent Born approximation. Nonzero spin Hall current is obtained for this homogenous system and the spin Hall conductivity is found to depend not only on the degree of the band nonparabolicity but also on the detailed properties of the scattering. With the same nonparabolic coefficient and electron density pertinent to a typical InAs 2D system, the surviving total spin Hall conductivity sigma(sH) appears to be an order of magnitude larger in the case of remote impurity scattering than that of the short-range scattering for Rashba coupling parameter alpha up to 6x10(-11) eV m.