Spectral analysis of Pr3+-, Sm3+- and Dy3+-doped transparent GeO2-BaO-TiO2 glass ceramics

In this paper, we present the photoluminescence properties of Pr3+-, Sm3+- and Dy3+-doped germanate glasses and glass ceramics. From the X-ray diffraction measurement, the host glass structure was determined. These glasses have shown strong absorption bands in the near-infrared (NIR) region. Compared to Pr3+-, Sm3+- and Dy3+-doped glasses, their respective glass ceramics have shown stronger emissions due to the Ba2TiGe2O8 crystalline phase. For Pr3+-doped glass and glass ceramic, emission bands centered at 530 nm (P-3(0)-> H-3(5)), 614 nm (P-3(0)-> H-3(6)), 647 nm (P-3(0)-> F-3(2)) and 686 nm (P-3(0)-> F-3(3)) have been observed with 485 nm (H-3(4)-> P-3(0)) excitation wavelength. Of them, 647 nm (P-3(0)-> F-3(2)) has shown bright red emission. Emission bands of (4)G(5/2)-> H-6(5/2) (565 nm), (4)G(5/2)-> H-6(7/2) (602 nm) and (4)G(5/2)-> H-6(9/2) (648 nm) for the Sm3+:glass and glass ceramic, with excitation at H-6(5/2)-> F-4(7/2) (405 nm) have been recorded. Of them, C-4(5/2)-> H-6(7/2) (602 nm) has shown a bright orange emission. With regard to the Dy3+:glass and glass ceramic, a bright fluorescent yellow emission at 577 nm (F-4(9/2)-H-6(13/2)) has been observed, apart from, F-4(9/2)-> H-6(11/2) (667 nm) emission transition with an excitation at 454 nm (H-6(15/2)-> I-4(15/2)) wavelength. The stimulated emission cross-sections of all the emission bands of Pr3+, Sm3+ and Dy3+:glasses and glass ceramics have been computed based on their measured full-width at half-maxima (FWHM, Delta lambda) and lifetimes (tau(m)). (C) 2008 Elsevier B.V. All rights reserved.