Spectral analysis of Pr 3+-, Sm 3+- and Dy 3+-doped transparent GeO 2–BaO–TiO 2 glass ceramics

Abstract

In this paper, we present the photoluminescence properties of Pr 3+-, Sm 3+- and Dy 3+-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 Pr 3+-, Sm 3+- and Dy 3+-doped glasses, their respective glass ceramics have shown stronger emissions due to the Ba 2TiGe 2O 8 crystalline phase. For Pr 3+-doped glass and glass ceramic, emission bands centered at 530 nm ( 3P 0→ 3H 5), 614 nm ( 3P 0→ 3H 6), 647 nm ( 3P 0→ 3F 2) and 686 nm ( 3P 0→ 3F 3) have been observed with 485 nm ( 3H 4→ 3P 0) excitation wavelength. Of them, 647 nm ( 3P 0→ 3F 2) has shown bright red emission. Emission bands of 4G 5/2→ 6H 5/2 (565 nm), 4G 5/2→ 6H 7/2 (602 nm) and 4G 5/2→ 6H 9/2 (648 nm) for the Sm 3+:glass and glass ceramic, with excitation at 6H 5/2→ 4F 7/2 (405 nm) have been recorded. Of them, 4G 5/2→ 6H 7/2 (602 nm) has shown a bright orange emission. With regard to the Dy 3+:glass and glass ceramic, a bright fluorescent yellow emission at 577 nm ( 4F 9/2→ 6H 13/2) has been observed, apart from 4F 9/2→ 6H 11/2 (667 nm) emission transition with an excitation at 454 nm ( 6H 15/2→ 4I 15/2) wavelength. The stimulated emission cross-sections of all the emission bands of Pr 3+, Sm 3+ and Dy 3+:glasses and glass ceramics have been computed based on their measured full-width at half-maxima (FWHM, Δ λ) and lifetimes ( τ m).