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Er3+-doped tellurite glasses with chemical compositions (in mol%): 55TeO2-35ZnO-(5+x)PbO-2Bi2O3-(2-x)Na2O-Er2O3 with x = 0; 0.5; 1.0; 1.5 and 2.0) were synthesized and explored their physical and optical properties. Density and refractive index were measured at room temperature and other physical properties such as ionic packing ratio, field strength, polaron radius, internuclear distance and molar refraction were derived. It was found that Na2O substitution by PbO causes both refractive index and glass density increase.

Two series of tellurite glasses with molar compositions of (55TeO 2 -2Bi 2 O 3 -(41-x) ZnO-2Na 2 O-xNd 2 O 3 (x=0.5, 1.0, 1.5, 2.0 and 2.5) and 55TeO 2 -2Bi 2 O 3 -(41-x) ZnO-xNa 2 O-2Nd 2 O 3 (x=1.0, 2.0, 3.0, 4.0, 5.0) were fabricated using melt quenching technique. Based on the measured densities, refractive indices and absorption spectra, physical and spectroscopic properties of these two-glass series are evaluated and compared. Whereas substitution of ZnO by Nd 2 O 3 causes the values of density and refractive index increase, the substitution of ZnO by Na 2 O has been shown to impact the glass density and refractive index in the opposite manner. Molar volume of both series increases with an increase of either Nd 2 O 3 or Na 2 O concentrations. In this regard, a dynamical model explaining the density and molar volume was proposed. Additionally, Judd-Ofelt theory was applied in order to predict the physical and laser properties of the two glasses series as a function of glass compositions, i.e., Judd-Ofelt parameters Ω t (t=2, 4, 6), branching ratios (β), calculated lifetimes (τ), the emission to exited state absorption intensity ratio (A em /A ESA ) and spectroscopic quality χ=Ω 4 /Ω 6 . Equations to relate χ with branching ratios for laser transitions 4 F 3/2 to 4 I J' (with J′ =9/2, 11/2, 13/2 and 15/2) were also derived.

This paper presents the effect of TiO2 addition on the physical and optical properties of TeO2-ZnO-Na2O glasses. For this study, glasses with the compositions of 63.16TeO2 - (31.57-x) ZnO – 5.26 Na2O – xTiO2 (where x = 1.06, 2.11, 3.16, and 4.22 mol%) were prepared with melt quenching technique. Glasses were characterized in order to obtained glass density, refractive index, and absorption spectra ranging from UV to IR regions. From these basic data, we have evaluated the values of molar volume, oxygen packed density, polaron radius, inter-ionic distance, field strength, and optical band gap. It was observed that incorporating TiO2 into the glasses to substitute ZnO have resulted in decreasing the values of density, inter-ionic distance, and field strength; and yet increasing molar volume, oxygen packed density and polaron radius. The structural units building the glass networks have also been evaluated.

Boro-tellurite glasses with composition 60TeO2- (30-x)ZnO- 5Bi2O3- 5TiO2- xB2O3 (where x = 0,2.5, and 5 mol%) have been successfully fabricated by melt quenching technique. FTIR characterization was carried out in range 400-4000 cm−1 using a KBr pellet method to study the glass chemical bond. The results show that several absorption peaks were recorded in range 400-4000 cm−1. However, most of the absorption peaks were detected in the region 400-1600 cm−1. It can be divided into 5 groups from 400-450 cm−1, 620-650 cm−1, 900-940 cm−1, and 1100-1300 cm−1. The main absorption peak of TZBT glass located at 620-650 cm−1, which is the fingerprint of TeO2 glass from Te-O vibration of TeO4 units. The addition of B2O3 components constructed a new absorption at 930 cm−1 and 1100-1300 cm−1. The absorption at 930 cm−1 belongs to B-O vibrations of BO4 units. While the absorption at 1100-1300 cm−1 relates to B-O vibrations of BO3 units. For further investigation, the deconvolution process was performed to discover the effect of the addition of B2O3 in the main absorption spectra. It was confirmed that six bands detected in the main absorption peak. The effect of B2O3 reduces the absorption band and shift the wavenumbers in TZBT glass.