The effect of ZnF2 on the near-infrared luminescence from thulium doped tellurite glasses

In the present study, the low OH content, thulium doped fluorotellurite glasses are defined as low-quenching materials. Two lines of evidence, lifetime and emission spectra measurements, have shown that the depletion of the H-3(4) state by cross relaxation processes was highly efficient. The links in question, together with the linear concentration-quenching dependence of the F-3(4) state, indicated the regime of fast diffusion processes. The addition of ZnF2 to a tellurite based host significantly improved self-quenching reduction especially for highly doped samples. The increase of the F-3(4) state lifetime value for a different ZnF2/ZnO ratio in the glass samples, fabricated inside a glove box, has been demonstrated and discussed.