Spatio-temporal dynamics of optically excited excitonic wavepackets in semiconductor quantum wells

Summary form only given. Optical excitation of a semiconductor quantum well leads to a built up of coherent polarization as well as charge carrier densities in the valence and conduction band. Ultrashort and spatially localized optical pulses make it possible to study the preparation, propagation and scattering of carrier wavepackets. Recent work has investigated the electronic transport phenomena for above bandedge excitation under the influence of phonons and interface roughness and describes microscopically the temporally resolved cross-over from the ballistic to the diffusive transport regime. In contrast, for excitation of bound electron-hole pairs, i.e. excitons with a larger oscillator strength, the coupling to the radiation field cannot be neglected and the coupling through the crystal lattice via acoustical phonons plays an important role in the formation and decay process of wavepackets. We present results for the spatio-temporal dynamics of quantum well excitons interacting with photons and phonons in a disordered landscape. The theory is based on a microscopic description for phonons, photons and disorder in a spatially inhomogeneous system.