We present a numerical study of the two-band semiconductor Bloch equat
ions in bulk GaAs under the influence of a short laser pulse. In our m
icroscopic approach, based on the nun-equilibrium Greens function (GF)
formalism, we show that within the random-phase approximation with a
dynamically screened potential the coherent carrier dynamics is strong
ly modified by a coupling of optical plasmons and interband polarisati
on.