BBGKY APPROACH TO NON-MARKOVIAN SEMICONDUCTOR BLOCH EQUATIONS

A density operator approach to generalized semiconductor Bloch equatio ns (SBE) for one-time observables which includes carrier-carrier scatt ering effects is presented. The theoretical concept is based upon the quantum generalization of the BBGKY hierarchy for the reduced density operators. Tile advantage of our method is its simplicity and transpar ence - to a large extent. derivations and physical approximations call be pel formed on the simplest level possible. that of a one-component system of spinless particles. We discuss various approximations for t ile incoherent terms in the Bloch equations which are related to carri er-carrier correlations, such as strong: coupling effects and tile bui ld-up of dynamical screening as well as self-energy effects. As a resu lt we obtain non-Markovian generalizations of the SBE.