Study on 2.0μm fluorescence of Ho-doped water-free fluorotellurite glasses

•Ho-TZNF60 glasses were made by specially-designed PCDH technique.•Mid-IR emission spectra were deeply probed experimentally.•The longest fluorescence lifetime at 2.04μm is presented in Ho-TZNF60 glass.•1.00Ho-TZNF60 glass is ideal material to develop Mid-IR fiber lasers. Ho3+-doped water-free fluorotellurite glasses with composition of 60TeO2–30ZnF2–10NaF (mol%, TZNF60) were made by using specially-designed physical and chemical dehydration technique. 2.04μm fluorescence (Ho3+: 5I7→5I8) was observed experimentally and presented in this paper: A broad bandwidth of ∼149nm, large simulated emission cross-section of 7.2×10−21cm2, and the longest reported fluorescence lifetime of ∼10ms among all the reported Ho3+-doped oxide glasses. Thanks to the absence of OH groups and low phonon energy with the addition fluorides into tellurite oxide glasses, 1.00Ho-TZNF60 glass demonstrates the maximum figure of merit (σem×τf) of 7.13×10−27m2s, thus regarded as a promising optical material for the development of 2.0μm fiber lasers.