Effect of heat treatment on the structural and optical properties of tellurite glasses doped erbium

► Tellurite glasses were prepared by conventional melt-quenching method. ► Effect of the heat treatment was investigated on the based glasses. ► Structural and optical properties were studied. ► Judd-Ofelt model is applied to Er absorption spectra. ► PL spectra and PL lifetime were recorded for all the samples at 1.53 μm.