Effect of substituting ZnO to ZnF₂ on Optical Properties of Nd³⁺/Tm³⁺ Doped Tungsten-Bismuth-Tellurite Glass

Present research explores the impact of varying ZnO and ZnF2 concentrations in Nd3+/Tm3+ doped Tungsten-Bismuth-Tellurite glass for fiber optic and solid-state application. Glasses with formula 60.97TeO2–6.7WO3–3.3 Bi2O3–0.03Nd2O3–1TmO–(28-x)ZnO–xZnF2 where x = 0, 7, 14, 21, 28 mol% is prepared using melt-quenching technique. The absorption and photoluminescene of the glass is measured using a UV-Vis-NIR absorption and Photoluminescence spectrometer. About eight absorption bands are evidenced, centred around 467, 525, 581, 687, 726, 793, 870, 1211, and 1691 nm, corresponding to respective REIs (Nd3+ and Tm3+ ions) transitioning from the ground to their excited state. The absorbance of Tm3+ centred around 1691 nm improved with higher ZnF2 contents (28% mol). Physical parameters such as density, molar volume, molar refractivity, and electronic polarizability are calculated. Seven prominent luminescence peaks of Nd3+ and Tm3+ have been identified centred around 509, 586, 611, 626, 648, 795, 800, and 890 nm. Highest luminescence enhancement is evident at 800 nm which corresponds to glass contained ratio of ZnO/ZnF2 at 3:1. These findings highlight the role of ZnF2 in altering the luminescence properties of the glass for fiber optics and solid-state laser applications.