germanium and fluorine-monoxide

Spectroscopic properties of rare earths in lead-free oxyfluoride germanate glasses were studied. The absorption and luminescence spectra of Eu(3+), Pr(3+) and Er(3+) ions were examined as a function of BaF₂ concentration and several spectroscopic parameters for rare earths were determined. The ratio of integrated luminescence intensity of the (5)D₀→(7)F₂ transition to that of the (5)D₀→(7)F₁ transition of Eu(3+) decrease significantly with increasing BaF₂ content. The absorption (Er(3+)) and emission (Pr(3+)) 'hypersensitive transitions' of rare earths are shifted in direction to shorter wavelengths with increasing BaF₂ content in glass composition. Emission spectra and their decays corresponding to the main (4)I₁₃/₂→(4)I₁₅/₂ laser transition of Er(3+) were also analyzed. Quite long-lived NIR luminescence of Er(3+) is observed for lead-free glass samples with low BaF₂ concentration.

Topics: Fluorine; Germanium; Glass; Luminescence; Metals, Rare Earth; Oxides

Er3+:Yb3+ co-doped oxy-fluoride glasses with composition of (50-x) GeO2.PbF2.WO3.(6 + x) CdF2.1.4Yb2O3.0.6Er2O3 (x = 10,20,30) were prepared. Their up-conversion fluorescence characteristics were investigated under excitation of 930 nm diode laser. Three strong fluorescence bands of Er3+ whose central wavelength lie in 543, 550 and 655 nm have been observed. The maximum phonon energy is obtained by measuring anti-stokes Raman shifts of the samples, and the up-conversion mechanism is briefly discussed. The influences of host materials composition on up-conversion efficiency are also discussed adopting the average electronegative difference and the cationic field strength of the host. It is found that relative small average electronegative difference and large cationic field strength of host benefit to energy up-conversion.

Topics: Cadmium; Erbium; Fluorescence; Fluorine; Germanium; Glass; Oxides; Spectrum Analysis, Raman; Ytterbium