doi: 10.1088/0268-1242/19/4/126We analyse the combined effect of high electric field and Coulomb interaction on spin transport in semiconductors. We concentrate on the experimentally relevant regime characterized by T lap TF (intermediate to degenerate), where TF = εF/kB is the Fermi temperature. By the careful analysis of the downstream spin diffusion length Ld, we (i) demonstrate that in this regime carrier-carrier interactions become important and (ii) introduce the 'semiconductor degenerate' regime, in which spin-transport properties of a degenerate semiconductor are substantially modified by applying a modest electric field. Finally we discuss how the electric field and Coulomb interaction concur to influence the magnetoresistance of...