  The transport properties of exciton-polaritons are studied with allowance for
their polarization. Both classical multiple scattering effects and quantum
effects such as weak localization are taken into account in the framework of a
generalized kinetic equation. The longitudinal-transverse (TE-TM) splitting of
polariton states which plays role analogous to the spin-orbit splitting in
electron systems is taken into account. The developed formalism is applied to
calculate the particle and spin diffusion coefficients of exciton-polaritons,
spin relaxation rates and the polarization conversion efficiency under the
conditions of the optical spin Hall effect. In contrast to the electron
systems, strong spin splitting does not lead to the antilocalization behavior
of the particle diffusion coefficient, while quantum corrections to spin
diffusion and polarization conversion can be both negative and positive
depending on the spin splitting value.
