The Physical, Optical, Photo and Radioluminescence Studies of Dy3+ Doped Zinc Barium Gadolinium Phosphate Glasses

The Dy2O3 doped phosphate glasses of chemical composition 10ZnO center dot 10BaO center dot 10Gd(2)O(3) center dot 70P(2)O(5), 10ZnO center dot 10BaO center dot 10Gd(2)O(3) center dot 69P(2)O(5) center dot 1Dy(2)O(3) and 10ZnO center dot 10BaO center dot 10GdF(3) center dot 69P(2)O(5) center dot 1Dy(2)O(3) were prepared by melt quench technique. The prepared glass samples were characterized through physical and luminescence properties such as density, molar volume, refractive index, FTIR, UV-Vis-NIR absorption spectra, photoluminescence excitation and emissions, radio-luminescence and life time. The J-O theory were analyzed to calculate the radiative properties such as radiative transition probabilities (A(R)), stimulated emission cross section (sigma(R)) and branching ratio (beta(R)). Total nine characteristics absorption peaks belong to Dy3+ ion at the 347, 386, 454, 750, 800, 896, 1089 and1674 nm respectively corresponding to transition from ground state H-6(15/2) to excited state M-4(15/2)+I-4(15/2), F-4(7/2)+I-4(13/2), I-4(15/2), F-6(3/2), F-6(5/2), F-6(7/2), F-6(9/2) and H-6(11/2) are observed in absorption spectra in the 300-1900 nm region. The photoluminescence and radio-luminescence emission spectra of the present glasses were recorded and found in good agreement with one another. The CIE 1931 chromaticity color coordinates were evaluated and it is found that these coordinates positioned in the white region with (x, y) = (0.39, 0.44) values for both oxide and oxyfluoride glasses. The florescence decay time from F-4(9/2) level was measured by monitoring the intense F-4(9/2) -> H-6(13/2) (573 nm) transition. The decay time is found to be non-exponential so the non-exponential curve was well fitted to Inokuti-Hirayama (IH) model for S = 6. The results obtained in present work demonstrate that the present glasses could be a good choice for use in white light solid state lighting applications.