A Comment on the Broadening of the Excitonic Molecule Band in CuCl

Abstract

The broadening of the excitonic molecule band in CuCl is studied from the giant two-photon absorption (GTA) measurements by a weak linearly polarized probe light beam under the simultaneous excitation around the same GTA by another strong pumping light beam of the orthogonal polarization to the probe beam. The width of the GTA line monitored by the probe light remains almost constant less than 0.3 meV under the strong irradiation of the pumping light. It is pointed out that the broadened width of the GTA band which have been observed by the strong one monochromatic beam experiments is not associated with the mutual collision between the really produced excitonic molecules.