title: Influence of two-pair continuum correlations following resonant excitation of excitons.
abstract: The memory structure induced by coherent transitions to the exciton-exciton scattering continuum is shown to have significant influence on spectrally resolved four-wave-mixing signals even under selective excitation of 1s excitons. Comparisons between experiments and calculations that account nonperturbatively for these quantum kinetic Coulomb correlations demonstrate large compensations between mean-field contributions and transitions to the two-pair continuum. Experiments with different polarizations of the laser pulses show that two-pair continuum correlations are responsible for delay-time dependent shifts of the excitonic emission as well as for substantial deformations of the line shape.
authors.affiliation: Institut für Festkörpertheorie, Westfälische Wilhelms Universität Münster, Wilhelm-Klemm-Strasse 10, D-48149 Münster, Germany.
authors.forename: V M
authors.initials: VM
authors.lastname: Axt
authors.forename: B
authors.initials: B
authors.lastname: Haase
authors.forename: U
authors.initials: U
authors.lastname: Neukirch