Introduction of BaF2 to titanate-germanate glasses doped with rare-earth ions evidenced by NIR luminescence spectroscopy

Abstract

A novel TiO2-GeO2-BaO-BaF2-Ga2O3 glasses doped with rare-earth were synthesized, and the impact of the substitution of BaF2 for BaO on properties has been investigated by luminescence spectroscopy. The IR absorption coefficient is extremely low, which is attractive for optical fibers emitting NIR radiation. Near-IR luminescence associated to the Er3+:4I13/2 → 4I15/2 (FWHM = 108 nm), Tm3+:3F4 → 3H6 (FWHM = 244 nm) and Ho3+:5I7 → 5I8 (FWHM = 179 nm) transitions are enhanced in the presence of BaF2. Luminescence lifetimes increase with increasing content of BaF2 in the glass composition. Fabricated optical materials with relatively high BaF2 content represent a good starting point for further investigations in the field of glass technology and modern photonics.