Photoluminescence of Pr3+, Sm3+ and Dy3+: SiO2–Al2O3–LiF–GdF3 glass ceramics and Sm3+, Dy3+: GeO2–B2O3–ZnO–LaF3 glasses

Abstract: In this paper, we present the absorption and photoluminescence properties of Pr3+, Sm3+ and Dy3+-doped transparent oxyfluoride alumino-silicate glass ceramics and Sm3+ and Dy3+-doped oxyfluoride germanate glasses. The X-ray diffraction (XRD) and differential thermal analysis (DTA) profiles of these glasses have been carried out, to confirm their structure and thermal stability. These glasses or glass ceramics have shown strong emission and absorption bands in visible and near-infrared (NIR) region. From the measured absorption spectra, Judd–Ofelt (J–O) intensity parameters (Ω 2, Ω 4 and Ω 6) have been calculated for all the studied ions. Compared to Pr3+, Sm3+ and Dy3+ doped glasses, their respective glass ceramics have shown stronger emissions due to LiGdF4 crystalline phase in alumino-silicate glass ceramics. For Pr3+ doped glass and glass ceramic, emission bands centered at 527nm(3P0→3H5), 610nm(3P0→3H6), 640nm(3P0→3F2), 678nm(3P1→3F3), 702nm(3P0→3F3) and 721nm(3P0→3F4) have been observed with 445nm(3H4→3P2) excitation wavelength. Of them, 640nm(3P0→3F2) has shown bright red emission. Emission bands of 4G5/2→6H5/2 (562nm), 4G5/2→6H7/2 (598nm), 4G5/2→6H9/2 (644nm) and 706nm(4G5/2→6H11/2) for the Sm3+: glass and glass ceramic, with excitation at 6H5/2→4F7/2 (402nm) have been recorded. Of them, 4G5/2→6H7/2 (598nm) has shown a bright orange emission. With regard to the Dy3+: glass and glass ceramic, a bright fluorescent yellow emission at 576nm(4F9/2→6H13/2) and blue emission at 485nm(4F9/2→6H15/2) have been observed, apart from 4F9/2→6H11/2 (662nm) emission transition for glass ceramic with an excitation at 388nm(6H15/2→4I13/2+4F7/2) wavelength. For germanate glasses, emission bands of 4G5/2→6H5/2 (564nm), 4G5/2→6H7/2 (601nm), 4G5/2→6H9/2 (644nm) and 705nm(4G5/2→6H11/2) for the Sm3+: glass, with an excitation at 6H5/2→4F7/2 (401nm) have been recorded. Of them, 4G5/2→6H7/2 (601nm) has shown a bright orange emission. With regard to the Dy3+: glass, a bright fluorescent yellow emission at 576nm(4F9/2→6H13/2) and blue emission at 482nm(4F9/2→6H15/2) have been observed, apart from 4F9/2→6H11/2 (661nm) emission transition with an excitation at 386nm(6H15/2→4I13/2+4F7/2) 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, Δλ) and measured lifetimes (τm ). [Copyright &y& Elsevier]