Quantum theory for the dynamic microstructure in correlated two-component systems far from equilibrium -- Application to x-ray scattering

We present a quantum theory for the dynamic structure factors in non-equilibrium, correlated, two-component systems such as plasmas or warm dense matter. Using this general framework, we derive expressions for effective local field corrections to the random phase approximation. The polarization function, which is needed as the input for the calculation of the structure factors, is calculated in non-equilibrium based on a perturbation expansion in the interaction strength. To make our theory applicable for x-ray scattering, a generalized Chihara decomposition for the total electron structure factor in non-equilibrium is derived. Examples are given for the special case of equilibrium and for a model bump-on-hot-tail distribution, as often encountered during laser heating of materials.