The effect of the exciton continuum on the exciton-exciton correlation

We present a numeric calculation of the exciton-exciton correlation for a o ne-dimensional semiconductor model with long-range Coulomb interactions, ta king into account the effect of the exciton continuum. We use the obtained correlation functions to calculate the time integrated intensity of the fou r wave miring signal. Changing the central frequency of the exciting pulses we observe changes in the profile and in the rise time of the time integra ted signal for negative delays in qualitative agreement with experimental r esults. Our results show theoretically how the exciton continuum affects th e coherence of four-particle correlations.