Yb-Doped Titanate-Germanate Glasses for Near-IR Luminescence Applications: Synthesis, Characterization, and the Influence of TiO Concentration.

In the framework of luminescent rare-earth-doped glasses for near-infrared applications, TiO-containing inorganic glasses have been recently demonstrated to be a promising alternative to commercially used high-phonon SiO-based glasses. This study investigates the effect of TiO concentration on the near-infrared spectroscopic properties of Yb ions in multicomponent titanate-germanate glasses. A series of glass samples in the xTiO-(60-x)GeO-BaO-GaO-YbO system (x ranging from 0 to 50 mol%) were synthesized using the melt-quenching technique. X-ray diffraction analysis confirmed the fully amorphous nature of the fabricated titanate-germanate samples. Fundamental spectroscopic properties of Yb-doped titanate-germanate system consisting of absorption spectra, near-IR emission spectra, and luminescence decay curves have been determined based on measurement using optical spectroscopy. The intensity of the emission band at 1 µm due to the F → F laser transition of Yb ions increases by over 2.3-fold (TiO as the network former) compared to a barium gallo-germanate sample without TiO. Our previous studies indicate that Yb-doped titanate-germanate glass is a promising optical material and could be successfully applied to laser technology.