Theory of Hall effect in two-dimensional giant Rashba systems

The weak-field Hall conductivity of disordered two-dimensional systems with strong Rashba spin-orbit interaction is studied in a self-consistent Born approximation. Explicit numerical results are obtained for scatterers with a Gaussian potential and for charged impurities. The singular behavior associated with a conelike crossing band appears only in the case of scatterers with a long-range Gaussian potential, which do not cause mixing with the outer band. In the case of more realistic scatterers such as charged impurities, the singularity is completely removed except the presence of a weak steplike feature. The Hall conductivity associated with the spin-Zeeman energy is also strongly reduced by interband mixing and generally remains much smaller than the orbital contribution.