Size-dependent homogeneous linewidth of Z3 exciton absorption spectra in CuCl microcrystals

Size-dependent homogeneous linewidth of Z3 exciton absorption spectra in CuCl microcrystals was measured at 2 K by the pump-and-probe spectroscopy. Observation of the hole burning gave us the homogeneous linewidth. The size-dependent part of the homogeneous linewidth is inversely proportional to the square of the radius of microcrystals. This dependence is explained by a simple model that a generated exciton dephases through the scattering at the irregular surface of microcrystals.