1˙ 23 μm emission of Er-doped water-free fluorotellurite glasses

摘要: To identify more efficient materials for 1·2 μm fibre optical amplifiers, we report on near-infrared emission centred at 1·23 μm from Er3+-doped water-free fluorotellurite glasses with the composition 60TeO2–30ZnF2–10NaF (TZNF60, mol%). Pumped by an OPO laser system at 523 nm, emission at 1·23 μm (Er3+:4S3/2→4I11/2 transition) was observed; the τf at 1·23 μm is 21·6–86·4 μs, arising from the optimized water-free surroundings and lower phonon energy arising from the addition of a large amount of fluoride into the tellurite-based host glass. 0·5 wt% Er2O3 doped TZNF60 glass is regarded as a promising material for the development of optical amplification and laser operation at the relatively unexplored 1·2 μm region as it has the highest quantum efficiency and the largest figure of merit among this group of Er-TZNF60 glasses.