Optical and physical properties of Er3+-doped oxy-fluoride tellurite glasses

In this manuscript we present the effects of ZnF2 concentration on the optical and physical properties of Er3+-doped oxy-fluoride tellurite glasses (7500 ppm Er2O3-(80−x)TeO2-xZnF2-20ZnO, where x = 5, 10, 15, 20, 25 and 30 mol%). In general, as the concentration of ZnF2 increases: (i) the thermal stability, the optical transparency window, and the lifetime of the 4I13/2 level increase; (ii) the density, the linear refractive index, the Rayleigh scattering loss, and the OH− ion concentration decrease; and (iii) the Er3+ ion emission cross section spectrum is quenched and the bandwidth is reduced. The 4I13/2 level lifetime increase may be associated with the luminescence re-absorption and the radiative transition (4S3/2 → 4I13/2) processes, since both processes may contribute to the 4I13/2 level population. The Er3+ ion emission cross section spectrum (at around 1550 nm) of oxy-fluoride tellurite glass containing 30 mol% of ZnF2 was very similar to those of Fluoride glasses.