Dependence of fluorescence properties on substitution of BaF 2 for BaO in barium gallo-germanate glass

Abstract

3.5 mol%, 6.5 mol%, 9.5 mol%, and 12.5 mol% BaF 2 were gradually substituted for BaO in 0.3 mol% Tm 2O 3 doped 12.5 BaO–12.5 Ga 2O 3–75 GeO 2 (BGG) glasses to study the effect of the substitution on the OH − elimination and emission properties. The FTIR spectral demonstrated that the substitution effectively eliminated OH − groups and 9.5 mol% BaF 2 was enough for the OH − elimination. The J–O parameters of all the samples were calculated according to J–O theory. The calculation showed that the Ω 2 parameter decreased monotonically with BaF 2 content increasing, while Ω 4 and Ω 6 did not change much. The radiative lifetime increased while BaF 2 content increased as well. The emission cross section of 3F 4 → 3H 6 transition was calculated by the F–L formula. However, it decreased with the gradual BaF 2 addition. Research Highlights ► OH − groups were eliminated by the substitution of BaF 2 for BaO in (BGG) glass. ► The optimal substitution level of BaF 2 was 9.5 mol% for OH − elimination. ► The Ω 2 parameter decreased monotonically by the elimination. ► The emission cross section of 3F 4 → 3H 6 transition was decreased by the substitution.