Propagation beating at the Na-bound exciton in CdS

Propagation of coherent small-area picosecond laser pulses in resonance wit h the acceptor-bound (I-1) exciton in CdS results in pronounced beating. Th e analysis in terms of the coupled Maxwell-optical Bloch equations demonstr ates the evolution of a Oct-pulse and gives a dephasing time of 65 ps. The beating likewise is described in the polariton picture that allows derivati on of the bound exciton dispersion.