Concentration dependent spectroscopic properties of Sm3+ doped borophosphate glasses

A new series of Sm3+ doped borophosphate glasses 50B(2)O(3) + 20Li(2)CO(3) + 10ZnO + 9SrCO(3) + (11 - x)P2O5 + xSm(2)O(3) (x = 0.1, 0.25, 0.5, 1 and 2 in wt%) have been prepared by following melt quenching technique. The structural and optical properties of the prepared glasses were characterized through XRD, FTIR, absorption, luminescence and decay spectral measurements. The XRD spectrum exhibit broad diffusion at lower angles which reveal the amorphous nature and the presence of various functional groups such as P-O-P bonds, B-O vibrations in BO3 units and P-OH and B-OH bonds in the title glasses were confirmed through the FTIR spectra. The nature of the metal-ligand bonding and the electronic band structure has been investigated using the absorption spectra. The Judd-Ofelt (JO) intensity parameters (Omega(2), Omega(4) and Omega(6)) were evaluated from the JO theory using the refractive index and the experimental oscillator strength values. The emission spectra exhibit four emission bands in the visible region corresponding to the (4)G(5/2) -> H-6(5/2), (4)G(5/2) -> H-6(7/2), (4)G(5/2) -> H-6(9/2) and (4)G(5/2) -> H-6(11/2) transitions by monitoring an excitation wavelength at 403 nm. The emission spectra have been characterized through Commission International de I'Eclairage (CIE) 1931 chromaticity diagram to explore the dominant emission from the studied glasses. The radiative parameters such as transition probability (A(R)), branching ratios (beta(R)) and stimulated emission cross-section (sigma(P)(E)) were obtained for the emission transitions using JO parameters and the results were discussed and compared with the reported literature. (C) 2015 Elsevier B.V. All rights reserved.