Ytterbium-doped yttrium oxysulfide (Yb:Y2O2S) has been synthesized by solid-state reaction with sulfide flux. Diffuse reflection and emission spectra have been measured in order to determine the crystal field splitting of Yb3+ ion in the YOS lattice. According to the crystal-field levels probed in the spectra, the crystal field splitting of 2G7/2 manifold of Yb3+ ion in YOS is 709 cm-1, which is large enough for the quasi-three-level laser operation of Yb3+ ion. Emission peak position, width, fu

A spatial distribution of diffuse reflectance produced by obliquely incident light is not centered about the point of light entry. The value of shift in the center of diffuse reflectance is directly related to the absorption coefficient \mu_{a} and the effective attenuation coefficient \mu_{eff}. \m