Heavily Er2O3 doped TeO2 based glass-ceramics with large grain size and high transparency for broadband ∼1.55 and efficient ∼3.5 μm fluorescence

In this work, heavily Er 2 O 3 doped TeO 2 glass was employed for the fabrication of transparent glass ceramics with broadband NIR and efficient MIR emissions. The simple composition of the glass was to minimize the refractive index difference between the glass and precipitated crystal to obtain high transmittance glass ceramics with large grain size. The heavily doping concentration was favor to obtain broadband NIR and efficient MIR emissions. The influence of the temperature and duration of the heat treatment on the size of the precipitated Er 2 Te 5 O 13 crystal was investigated. The transmittance of the glass-ceramics was higher than 80%/mm when the size of the precipitated crystal increased up to 6.82 μm. The XRD patterns of the surface and bulk glass-ceramic demonstrated the crystallization was surface indued crystallization. The NIR and MIR fluorescence properties were discussed. • Fabricated the high transparence glass-ceramics with large grain sizes. • Demonstrated the crystallization of TeO2 based glass was surface induce crystallization. • Highly efficient ∼3.5 μm emissions were obtained from Er3+ heavily doped TeO2 based glass-ceramics.