M.Elisa, I.C. Vasiliu, C.E.A.Grigorescu, B. Grigoras, H. Niciu, D. Niciu, A. Meghea, N. Iftimie, M. Giurginca, H.J.Trodahl, M.Dalley, Optical and structural investigation on rare-earth-doped aluminophosphate glasses , J. Opt. Mat., 28/6-7 (2006) 621-625

Title: Optical and structural investigations on Cd-S-Se-doped aluminophosphate glasses

Abstract: Aluminophosphate glasses doped with semiconductor CdSxSe1-x crystallites were produced by a wet non-conventional method that provides a high optical homogeneity of the glass. The samples belong to the oxide systems: Li-20-BaO-Al2O3La2O3-SiO2-P2O5 (SDG1) and Li2O-Na2O-BaO-Al2O3-La2O3-SiO2-P2O5 (SDG2) to which we added CdS0.5Se0,5 1 % Wt. (0.9 % mol.) and ZnO 1 % wt. (1.5 % mol.). The UV-VIS-NIR transmission spectroscopy revealed the shift of the transmission edge, depending on the temperature and the duration of annealing. As a general trend, the higher the temperature and the duration of the annealing process the more significant the shift of the transmission edge to higher wavelengths in the visible range. Consequently, the glass changed from colourless to red that indicates the presence of CdS0.7Se0.3 crystallites in the vitreous phosphate matrix, as also indicated by transmission electron microscopy analysis (TEM). Raman spectra obtained by Ar+ laser excitation at 514.5 nm, showed first and second order scattering lines from CdS0.7Se0.3. The device SPIRICON LBA 300 provided information regarding the dispersal of the crystallites in the host aluminophosphate glass. Thus, by a diode laser excitation at 625 nm, we analyzed relative intensity profile of the emergent beam from the doped-glass samples and we were able to estimate the crystallites dispersal in these vitreous materials.

Key words phosphate glasses; crystallites; semiconductors