Influence of carrier correlations on the excitonic optical response including disorder and microcavity effects

A model study of the characteristic signatures of carrier-correlation effec ts on the excitonic differential absorption spectra in semiconductors is pr esented. Using an effectively one-dimensional tight-binding system Coulomb- induced carrier-correlations up to third-order in the optical field are tre ated without additional approximations. To illustrate the influence of the different many-body contributions excitonic differential absorption spectra are computed for Various polarizations and pump-probe time delays. The sim ultaneous influence of energetic disorder and correlations on the different ial absorption spectra is discussed. Also presented are numerical results f or the case when the semiconductor system is placed inside a microcavity in the strong-coupling regime. Tt is shown that the correlations induce chara cteristic signatures in the normal mode spectra.