Enhanced 2.7 μm emission of Er/Pr-codoped water-free fluorotellurite glasses

摘要: Using physical and chemical dehydration technique and traditional melting and quenching method, we fabricated a group of Er/Pr-codoped water-free fluorotellurite glasses with composition of 60TeO2–30ZnF2–10NaF (TZNF60, mol%). The lifetime τf of 4I11/2 → 4I13/2 transition, directly measured under the excitation by an optical parametric oscillator (OPO) laser system at 978 nm, in Er/Pr codoped fluorotellurite glasses is 1.37–1.55 ms, longer than that of Er-doped tellurite oxide (215 μs) and Er-doped fluorotellurite glasses (1.07 ms). The introduction of Pr3+ ions into Er-doped system increases the emission intensity at 2.71 μm (Er: 4I11/2 → 4I13/2) and emission cross section as well. These advances partially arise from the absence of OH groups and low phonon energy with the addition of large amount of fluorides into oxide-based host glasses. With the high quantum efficiency and large figure of merit, Er/Pr …