Spin transport in a two-dimensional tight-binding system with Rashba and Dresselhaus spin-orbit interactions in the presence of static random disorder

Abstract

The longitudinal charge and spin conductivities for a two-dimensional system with random static disorder are investigated in the presence of Rashba and Dresselhaus spin-orbit interactions. The Matsubara Green function technique is used to determine the relaxation time for the impurity scattering and the charge and spin conductivities are obtained by employing the Kubo formalism. It is shown that the spin and charge conductivities are enhanced by the Rashba and Dresselhaus spin-orbit interactions while they are reduced by the presence of impurities. Finally, the effects of Rashba and Dresselhaus interactions on the ratio of longitudinal spin conductivity to charge conductivity are studied.