Heavy metal glasses and transparent glass-ceramics: preparation, local structure and optical properties

Abstract

Heavy metal oxide and oxyfluoride lead silicate glasses doped with rare-earth ions were prepared. Next, they were heat treated in order to obtain transparent glass-ceramics. The rare-earths as optically active ions were limited to trivalent Eu 3+ and Dy 3+ . Correlation between the local structure and the luminescence properties of Eu 3+ and Dy 3+ ions in the studied glass and glass-ceramic systems was examined using X-ray diffraction, FT-IR and optical measurements. Especially, the ratio of integrated emission intensity of the 5 D 0 – 7 F 2 transition to that of the 5 D 0 – 7 F 1 transition of Eu 3+ , defined as the luminescence intensity ratio R (Eu 3+ ) as well as the ratio of integrated emission intensity of the 4 F 9/2 – 6 H 13/2 transition to that of the 4 F 9/2 – 6 H 15/2 transition of Dy 3+ , defined as the luminescence intensity ratio Y/B (Dy 3+ ), have been analyzed in details. Their values are reduced due to part incorporation of rare-earth ions into cubic β-PbF 2 crystalline phase. The excitation and luminescence spectra of rare-earth ions in glass samples before and after heat treatment are presented and discussed in relation to potential application in optoelectronics.