Feedback and memory in kinetic equations of highly excited semiconductors

The memory kernels of kinetic equations in highly excited semiconductors in ultra short laser pump experiments are investigated with respect to a many-body treatment at each point on the time scale. This method results in a shift and a decay of the time dependent mean field (TDMF) states. Involving these effects, a generalized form of kinetic equations is derived, utilizing the internal Π2N ⊗ U(2) symmetry of the highly excited semiconductor.