Optical characterization of Tm(3+) doped Bi(2)O(3)-GeO(2)-Ga(2)O(3) glasses in absence and presence of BaF(2)

In this paper, Two new Bi(2)O(3)-GeO(2)-Ga(2)O(3) glasses (one presence of BaF(2)) doped with 1mol% Tm(2)O(3) were prepared by melt-quenching technique. Differential thermal analysis (DTA), the absorption, Raman, IR spectra and fluorescence spectra were measured. The Judd–Ofelt intensity parameters, emission cross section, absorption cross section, and gain coefficient of Tm(3+) ions were comparatively investigated. After the BaF(2) introduced, the glass showed a better thermal stability, lower phonon energy and weaker OH(−) absorption coefficient, meanwhile, a larger ~1.8 μm emission cross section σ(em) (7.56 × 10(−21) cm(2)) and a longer fluorescence lifetime τ(mea) (2.25 ms) corresponding to the Tm(3+): (4)F(3) → (3)H(6) transition were obtained, which is due to the addition of fluoride in glass could reduce the quenching rate of hydroxyls and raise the cross-relaxation ((3)H(6) + (3)H(4) → (3)F(4) + (3)F(4)) rate. Our results suggest that the Tm(3+) doped Bi(2)O(3)-GeO(2)-Ga(2)O(3) glass with BaF(2) might be potential to the application in efficient ~1.8 μm lasers system.