  We evaluate the non-equilibrium spin polarization induced by an applied
electric field for a tight-binding model of electron states at oxides
interfaces in LAO/STO heterostructures. By a combination of analytic and
numerical approaches we investigate how the spin texture of the electron
eigenstates due to the interplay of spin-orbit coupling and inversion asymmetry
determines the sign of the induced spin polarization as a function of the
chemical potential or band filling, both in the absence and presence of local
disorder. With the latter, we find that the induced spin polarization evolves
from a non monotonous behavior at zero temperature to a monotonous one at
higher temperature. Our results may provide a sound framework for the
interpretation of recent experiments.
