Search

In this study, we have reported on the effect of the rare earth oxides on the radiation protection performance of the tellurite glasses. In order to determine the effect of rare earth oxides on the radiation shielding properties of tungsten oxide (WO3) modified tellurite glasses, three rare earth element oxides (Nd2O3, Yb2O3, and Er2O3) have been selected. The glass systems have been synthesized using the traditional melt quenching method and were doped with the different amount (1 %, 3 %, 5 %) of the oxides of rare earth elements (Nd2O3, Yb2O3, Er2O3). The linear attenuation coefficient, mass attenuation coefficient, half value layer, and effective atomic number of the synthesized samples were experimentally measured for 662, 1,173 and 1,332 keV gamma-ray energies which were emitted from 137Cs and 60Co radioactive sources. Measurements were conducted in narrow beam transmission geometry using a NaI(Tl) scintillation detector. In addition, all these parameters were calculated theoretically using the WinXCOM program in the energy region of 0.015–15 MeV. The addition of different types and amounts of rare earth oxides to the tellurite glass system was found to significantly enhance the radiation protection performance of the glasses. In particular, it was found that the radiation shielding characteristics of the glasses improved with increasing amount of rare earth doping, the TWYb5 glass system had the best radiation shielding properties, and there was a trend among the doped rare earth oxides in the form of Yb > Er > Nd according to their radiation shielding performance. [ABSTRACT FROM AUTHOR]

Quaternary based tellurite glasses in the composition 75TeO 2 -10ZnO-(15-x)Nb 2 O 5 -xLa 2 O 3 (0 ≤ x ≤ 9 mol%) were synthesized through the melt-quenching method. X-ray diffraction (XRD), Energy dispersive X-ray (EDX) alongside color mapping images, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), Raman, Differential scanning calorimetry (DSC), UV–Vis absorption and DC conductivity studies were carried out to comprehend the influence of both Nb5+ and La3+ ions on the structural dependent properties of the glasses. Both XRD and DSC patterns have affirmed the amorphous nature of all the glasses. XPS studies asserted the stable oxidation states of all the constituent elements of the glasses. The Raman and FTIR analyses emphasized that the TZNL glasses are comprised of TeO 3 , TeO 3+1 , TeO 4 and NbO 6 units. The DSC analysis disclosed that the inclusion of La 2 O 3 content in the place of Nb 2 O 5 has improved the thermal stability (ΔT) of the glasses and also prevented the crystallization. DSC studies affirmed that these glasses have exhibited higher thermal stability, suggesting that these glasses might useful for optoelectronic devices and optical fiber drawing applications. The optical band gap (E opt) and Urbach energy (ΔE) of these glasses were observed to be non-linearly varied with the addition of La 2 O 3 content. DC conductivity (σ) was observed to be decreased and the activation energy (E act) was found to be increased with increasing La 2 O 3 content. [ABSTRACT FROM AUTHOR]

Glasses in the TeO2–Ga2O3–M2O (M═Li, Na, or K) systems were synthesized by a melt‐quenching technique. The glass forming areas were delimited for each system. Systematic analyses were performed on two series of samples—the first one with a constant TeO2/Ga2O3 ratio of 85/15, that is, [(TeO2)0.85(Ga2O3)0.15]100−x[M2O]x with 0 ≤ x ≤ 25 (with a step of 5 mol%), the second one with a constant alkaline oxide concentration of 10 mol%, that is, [TeO2]90‐y[Ga2O3]y[M2O]10 with 5 ≤ y ≤ 15 (with step of 2.5 mol%). The values of the glass transition temperature, density, and optical transmission parameters (the positions of short‐ and long‐wavelength absorption edge and the maximum transmittance value) were determined. The changes in these parameters were studied for varying glass compositions. In addition, the values of refractive index were measured at various wavelengths across the whole transparency region reaching from the visible up to the mid‐infrared range. [ABSTRACT FROM AUTHOR]

This study investigated the radiation shielding performance of the xBaO-(30-x)TeO2-35Bi2O3-35B2O3 glass system, where x = 5, 10, 15, 20 and 25, using Phy-X/PSD software and MCNPX Monte Carlo code. Key radiation shielding indicators, including attenuation coefficients, half value layer (HVL), tenth value layer (TVL), effective atomic number (Zeff), mean free path (MFP), and build-up factors, were measured within the energy range of 0.015–15 MeV. Further, the study assessed the glasses' capacity to block fast neutrons, using the fast neutron removal cross-section (ΣR) as a metric. The results showed that gamma shielding effectiveness follows the order: BaTBiB-1 < BaTBiB-2 < BaTBiB-3 < BaTBiB-4 < BaTBiB-5 at all photon energies. Additionally, the ΣR values for BaTBiB-1 to BaTBiB-5 glasses were 0.10179, 0.10263, 0.10362, 0.10581, and 0.10623 cm−1, respectively. Therefore, the findings demonstrate that including BaO enhances the gamma and neutron shielding characteristics of tellurite glasses, making them valuable for radiation-related applications.

Expanding gain bandwidth into the L-band for erbium-doped fiber amplifiers (EDFAs) is a crucial strategy to overcome limitations in prevalent C-band focused commercial silica-based EDFAs, significantly boosting optical network transmission capacity. Herein, we synthesized Er3+-doped broadband near-infrared emission tellurite glasses utilizing the melt quenching process, systematically exploring the impact of ZnCl 2 on the glass structure and optical properties. The 82TeO 2 –3Nb 2 O 5 –15ZnCl 2 –3Er 2 O 3 (TNZ15) glass emerged as a standout candidate for broadband amplifiers around wavelength at 1.55 μm. With escalating ZnCl 2 concentration, a discernible red shift in the emission peak wave lines was observed, accompanied by an expansion of the full width at half maximum (FWHM) from 98 nm to 106 nm. Noteworthy characteristics of all samples included exceptional thermal stability and elevated near-infrared (NIR) transmittance. Application of the Judd-Ofelt (J-O) theory facilitated the calculation of J-O parameter intensity, providing deeper insights into the optical behavior of the materials. Finally, the evaluation of TNZ15 planar optical waveguides, employing the vertical top pumping mode of two 980 nm LEDs, encompassed both the C-band (1530–1565 nm) and the L-band (1565–1625 nm). The results underscore the potential of TNZ15 glass as a promising gain material for broadband optical amplifiers and lasers, offering valuable insights into the development of next-generation optical amplification technologies. [ABSTRACT FROM AUTHOR]

The melt quenching procedure has been followed to synthesize transparent Tb3+ singly activated and Tb3+/Eu3+ co-activated TeO2–WO3–K2O–ZnO–Bi2O3 (TWKZBi) glasses. The structural characteristics of the prepared TWKZBi glass samples were examined through x-ray diffraction. The existence of functional units corresponding to the different vibrations has been examined via Raman spectroscopy. The photoluminescent characteristics and energy transfer (ET) analysis in the Tb3+/Eu3+ co-activated TWKZBi glasses were investigated in depth. Several emission peaks have been observed in Tb3+ doped TWKZBi glasses under n-UV and blue excitations and the maximum luminescent intensity has been detected for 2.0 mol% of Tb3+ doped TWKZBi glass sample. The emission spectra of co-doped Tb3+ and Eu3+ ions in the TWKZBi glasses have been studied, and the maximum ET efficiency is found to be 32.82% under n-UV excitation. The ET from sensitizer (Tb3+) to activator (Eu3+) ions happen through dipole–dipole interaction, as confirmed by Dexter's and Reisfeld's approximation. The colour-tunable emission in the prepared glass samples can be achieved via varying the content of activator ions. The decay profiles for the 5D4 level of Tb3+ ions diminish with varying the concentration of Eu3+ ions, confirming the ET from Tb3+ to Eu3+ ions. Furthermore, temperature-dependent photoluminescence studies show that the Tb3+/Eu3+ co-doped TWKZBi glasses have good thermal stability. All the aforementioned results reveal the suitability of the Tb3+/Eu3+ co-activated TWKZBi glass samples for photonic applications. [ABSTRACT FROM AUTHOR]

The melt quenching technique was used to create a ternary (90-x) TeO2 - xPbO - 10ZnO glass system (x = 0, 10, 20, 25, 30, 35, and 40 mol%). The X-ray diffraction (XRD) technique is used for improving the amorphous nature of the glass samples. In addition, to examine the structural characteristics of the glass samples, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy are used. Raman spectroscopy was used to evaluate the impact of PbO on the glass structure. A strong frequency peak at 729.63-774.69 cm-1 was detected in the Raman spectra, indicating that the TeO4 and TeO3/TeO3+1 structural units make up the majority of the glass network. The TeO3/TeO3+1 structural unit contain non-bonding oxygen molecules that are stretched in the Pb-O, Zn-O, Te-O, and Te-O-Te bridging configurations, vibrations, and Raman spectra. [ABSTRACT FROM AUTHOR]

This study investigated the radiation shielding performance of the xBaO-(30-x)TeO2-35Bi2O3- 35B2O3 glass system, where x = 5, 10, 15, 20 and 25, using Phy-X/PSD software and MCNPX Monte Carlo code. Key radiation shielding indicators, including attenuation coefficients, half value layer (HVL), tenth value layer (TVL), effective atomic number (Zeff), mean free path (MFP), and build-up factors, were measured within the energy range of 0.015–15 MeV. Further, the study assessed the glasses’ capacity to block fast neutrons, using the fast neutron removal cross-section (ΣR) as a metric. The results showed that gamma shielding effectiveness follows the order: BaTBiB-1 < BaTBiB-2 < BaTBiB-3 < BaTBiB-4 < BaTBiB-5 at all photon energies. Additionally, the R values for BaTBiB-1 to BaTBiB-5 glasses were 0.10179, 0.10263, 0.10362, 0.10581, and 0.10623 cm−1, respectively. Therefore, the findings demonstrate that including BaO enhances the gamma and neutron shielding characteristics of tellurite glasses, making them valuable for radiation-related applications. [ABSTRACT FROM AUTHOR]

Vanadium doped lithium telluro-borate (LTB) glasses of the composition (20-x)Li2O-20TeO2-60B2O3-(x)V2O5 (x = 0, 0.5, 1, 1.5 and 2 in mol %) were synthesised by melt quenching technique. The structural, optical, physical, electrical and radiation shielding parameters of the prepared glasses were investigated to determine the effect of vanadium in the LTB glass matrix. Density of LTB glasses were found to increases from 2.52 to 2.98 g/cm3 under addition of vanadium oxide and certain density derived structural parameters were studied. XRD pattern confirms the amorphous nature of the pristine and doped LTB glass. FTIR spectra shows the presence of various bonds in the vanadium doped LTB glasses. The direct optical bandgap (Eg) decreases due to the addition of V2O5 and leads to creation of defects in the LTB glasses thereby increasing the Urbach energy (Eu). Physical parameters like refractive index (n), molar refractivity (Rm), reflection loss (Lr), molar electronic polarizability (αm), transmission coefficient (T) and metallization criteria (M) were calculated. The electrical properties including dielectric constant (εʹ), conductivity (σ) and activation energies (Ea) were analysed and observed that Ea decreases under the addition of vanadium to the glass network proving the enhancement in electrical conductivity. Radiation shielding parameters such as MAC, LAC, HVL, TVL, MFP, R, ACS, ECS, Neff, Zeff, and Ceff were calculated using Phy-X/PSD and LTB_2V with the highest V2O5 additive shows enhanced result in gamma radiation shielding.

New In2O3-doped phosphate zinc tellurite glasses synthesized using melt-quenching method were investigated. It was observed that the synthesized glasses exhibit transparent properties. Densities of synthesized glasses changed significantly related to the doping ratio of In2O3. This implies that radiation shielding abilities can be enhanced. In other respects, the almost linear elevation in molar volume values indicated that the glass network expanded as a result of the ZnO/In2O3 translocation. As the additive ratio increases, the optical band gap value increases from 2.96 eV to 3.47 eV, while the Urbach energies decrease from 0.350 eV to 0.180 eV. In2O3 contribution has a regulatory effect on the structure of phosphate zinc tellurite glasses. In phosphate zinc tellurite glasses evaluated in terms of radiation shielding properties, it was observed that the In2O3 additive contributed significantly to the shielding properties and the glass with the best radiation shielding was 6 mol% In2O3 doped glass. It is obvious that by raising the density values of the produced glasses, the ZnO/In2O3 translocation in phosphate zinc tellurite glasses enhanced their radiation shielding properties.

A series of glasses based on (80-y) TeO2-20 BiCl3-y RE2O3 (y = 0, 0.6 mol%; RE = Nd, Sm, Dy, and Er) were prepared. The thermal stability of the glass was determined by differential scanning calorimetry (DSC). The density and optical energy values of the prepared glass increased in the order of Sm2O3, Nd2O3, Dy2O3, and Er2O3. In addition, the glass doped with Er2O3 had the highest refractive index values compared to the other samples. Subsequently, Judd–Ofelt parameters (Ω2, Ω4, and Ω6) were obtained for the family of RE3+ trivalent rare-earth ions introduced as dopants in a tellurite glass. These parameters were calculated from the absorption spectra for each RE3+. The structures were studied by Raman spectroscopy deconvolution, which determined that TeO4, TeO3, TeO3+1, BiO6, and BiCl6 units had formed. In addition, the structural changes in the glass are related to the intensity ratio of TeO4/TeO3, depending on the type of rare-earth. For the optics and Judd–Ofelt parameters, the ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optics fibers, a solid laser material. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report a correlation outcome for mechanical and gamma-ray transmission properties of tellurite glasses by increasing tungsten(vi) oxide concentration in glass structure. The mechanical properties as well as Poisson’s ratio (σ) of the studied glasses are estimated by applying Makishima–Mackenzie model. Gamma-ray attenuation properties using various fundamental parameters are determined in 0.015–15 MeV energy range. Poisson’s ratio (σ) decreased from 0.43017 to 0.42711, while all elastic moduli increased linearly with the molar increment of either [WO3] or [TeO2] in the molecular structure of the glass network. Moreover, gamma-ray attenuation properties are enhanced as a function of increasing WO3 substitution amount from 30 to 50% mol in the glass structure. Half-value layer values at 15 MeV are found to be between 2.648 and 2.8614 cm. I4 samples with a composition of 20TeO2–50WO3–30GdF3 and density of 6.0530 g/cm3 was found to have superior material properties in terms of elastic and gamma-ray attenuation properties. It can be concluded that maximized WO3 contribution into the tellurite glasses may be considered as a critical tool in terms of establishing a symmetry between mechanical and gamma-ray attenuation properties for high-density tellurite glasses for their potential utilization in nuclear waste management, radiation shielding, and radioactive source transportation purposes.

In this work, we studied, the vibrational and the thermal properties of the Tl2O–TeO2, V2O5–TeO2 and Tl2O–V2O5–TeO2 glass-forming systems by means of Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC). Thermal properties, such as the glass transition temperature (Tg), thermal stability (S), and thermodynamic fragility (F), were determined and correlated with the structural characteristics of the glasses. The binary glass-forming system Tl2O–TeO2 exhibits the transformation of TeO4 trigonal bipyramids into TeO3 trigonal pyramid units due to the presence of Tl2O. The decreasing trend of Tg with Tl2O content, along with the increase of the thermodynamic fragility, indicates that the structure becomes less interconnected and floppier. Concerning the V2O5–TeO2 glass system, we observed that V2O5 causes structural modifications in the TeO2 sub-network by changing the coordination number of Te atoms. Furthermore, the glass rigidity reduces as indicated by the glass transition temperature variation with composition. We also found that the 0.5V2O5–0.5TeO2 glass exhibits the highest resistance to thermal shocks and possesses the most rigid network. Concerning the structure of the ternary glass-forming Tl2O–TeO2–V2O5 system, the incorporation of Tl2O into the mixed vanadate–tellurite glasses decreases the glass transition temperature implying that Tl2O acts as a network modifier affecting the network's rigidity. The decreasing trend of the thermodynamic fragility indicates that the glass network becomes more rigid. Finally, the significantly high values of thermal stability reveal that the ternary glass-forming system can be considered as a glass with superior resistance against thermal shocks making it an ideal candidate for relevant technological applications. [ABSTRACT FROM AUTHOR]

This study investigates the effect of substituting tungsten(vi) oxide/gadolinium(iii) fluoride in tellurite glasses whose densities varies from 5.0879 to 5.3246 g/cm3 on gamma-ray absorption properties. A range of fundamental absorption parameters, including attenuation coefficients, half-value layer thicknesses, effective atom and electron numbers, effective conductivity, exposure, and energy absorption buildup factors, were studied for five different glass samples with varying substitution ratios. The ratio of tungsten(vi) oxide to gadolinium(iii) fluoride varied between 0 and 20 mol%, as well as the TeO2 ratio in the composition was maintained between 90 and 80 mol%. The sample with the composition of 80–20 mol% TeO2/WO3, which attained the maximum density value with 20 mol% WO3 addition, showed the highest gamma-absorption capabilities based on the obtained findings in the range of 0.015–15 MeV. In consideration of the mechanical and physical properties of WO3 in tellurite glasses, it can be concluded that WO3 incorporation is a crucial monotonic process that may be utilized to further improve the properties of glass shields.

We report the role of the chemical modifications on various gamma-ray attenuation properties of four different tellurite glasses reinforced through WO3. The chemical compositions and glass densities are used in terms of determining some critical attenuation properties, such as linear and mass attenuation coefficients, half value layer, and effective atomic number values. Based on the rise in density, it was determined that the maximum concentration of WO3 also resulted in a significant change in the overall gamma-ray absorption properties, when all of the study’s findings were examined. It was observed that the glass sample, in which TeO2 and WO3 were 40 mol%, had the highest density. It was found that this glass with the highest density has the highest linear attenuation coefficient and mass attenuation coefficient and the lowest half value layer among the four samples specified. This demonstrates that WO3 inclusion is a functional component that may be used in tellurium glasses and is a suitable material for situations requiring increased gamma-ray absorption properties.

We report the symmetry of mechanical and gamma-ray attenuation properties for some tellurite glasses through elastic moduli, mechanical, and transmission properties as a function of varied WO3 amount in glass configuration. Four glass samples, along with different molar compositions as well as WO3/GdF3 substitution ratios, are investigated. Transmission properties using several essential parameters, such as attenuation coefficients, half-value layers, effective atomic numbers, effective conductivity, and buildup factors, are calculated in the 0.015–15 MeV energy range. Moreover, elastic moduli and Poisson's ratios (σ) of the studied glass are calculated using the Makishima–Mackenzie model. The M4 sample with the highest WO3 addition is found with superior photon attenuation properties among the glasses investigated. Poisson's ratio (σ) is increased, while all elastic moduli are decreased. Young's modulus is reported as 62.23 GPa and 36.45.37 GPa at the highest and lowest WO3 mol%, respectively. It can be concluded that WO3 is a functional and monotonic tool in ternary-tellurite glasses for multiple modifications and enhancement purposes on gamma-ray attenuation, elastic moduli, and mechanical properties. It can also be concluded that increasing the WO3 amount in tellurite glasses may be considered a tool in terms of providing symmetry for mechanical and gamma-ray attenuation properties. [ABSTRACT FROM AUTHOR]

In this investigation, the photons shielding factors for tungsten tellurite glasses with the yWO3–(90 − y)TeO2–10Na2O (y = 05, 10, 15 and 20 mol%), were reported. The penetration and attenuation factors for this system at various energies were reported using the Phy-X/PSD program. With increasing energy, it is observed that the linear attenuation coefficient (LAC) values, which range from 1.087–0.234 cm−1 (for TWN1) to 1.354–0.248 cm−1 (for TWN4), decrease exponentially. The LAC values were found to increase with the addition of WO3 from 1.087 to 1.354 cm−1 at 0.245 MeV and from 0.515 to 0.586 cm−1 at 0.444 MeV. Additionally, the greater potential for photon interactions at higher WO3 concentrations was indicated by the findings of the effective atomic number (Zeff) calculation. According to the obtained results, the maximal Zeff occurred at 0.284 MeV, which is equivalent to 32.53 for TWN1 and 36.89 for TWN4. The half value layer (HVL) for the samples under consideration between 0.245 and 1.458 MeV has been determined using the Phy-X/PSD. The HVL results demonstrated that at 0.284 MeV, more gamma rays are shielded whereas the potential of photon shielding decreases as energy increases. The tenth value layer (TVL) increased with rising energy and decreased with rising WO3 concentrations. TVL for TWN4 is the lowest (1.701 cm at 0.245 MeV and 9.284 cm at 1.458 MeV). [ABSTRACT FROM AUTHOR]

In this article, we present research on the influence of erbium ions on the structure and magneto-optical properties of 70TeO2-5XO-10P2O5-10ZnO-5PbF2 (X = Pb, Bi, Ti) tellurite glass systems. Structural changes occurring in the glasses during doping with erbium ions were investigated using positron annihilation lifetime spectroscopy (PALS) and Raman spectroscopy. The X-ray diffraction (XRD) method was used to confirm the amorphous structure of the investigated samples. Based on the Faraday effect measurements and calculated values of Verdet constant, the magneto-optical properties of the glasses were determined. [ABSTRACT FROM AUTHOR]

Previous works have been already reported on multiphonon-assisted non-resonant energy transfer in Ce3+-Er3+-doped tellurite glasses. However, it is not clear the mechanism of the radiative emission of Er3+ centered at 1530 nm. In this paper, we reported a better understanding of the mechanism of interactions between those two rare-earth ions via a systematic study. For that, we will explore the energy transitions between Ce4+/Ce3+ and Er3+ ions in a tungsten-tellurite glass to both emission (in the near infrared) and upconversion (in the visible) spectrum. Here, Ce4+ and Ce3+ were obtained in an Er3+-doped tellurite glasses via the addition of different concentrations of CeO 2 as part of the composition of the samples. Emission spectrum, under a 980 nm excitation, giving rise to a series of interactions between Ce3+↔Er3+ resulting in: (i) a subtle increase of the Er3+ emission intensity in the near-infrared region for 0.1 mol% of CeO 2 , and then a decrease in the emission for higher CeO 2 concentration in both cases without any significant increase in the bandwidth, and (ii) a decrease of the visible upconversion emission intensity with the addition of CeO 2. Such interactions are achieved via a coupling yielding and energy transfer from both rare-earth ions. [ABSTRACT FROM AUTHOR]

The shielding and spectroscopic properties of Pr + 3 and Pr3+/Ho3+-codoped tellurite glass were investigated. The intensity parameters (Ω2 = 3.24-, Ω4 = 1.64-, Ω6 = 1.10 × 10−20 cm2) as well as the radiative lifetimes of 3F4 + 5S2 and 5I6 excited states of Ho3+ ions were equal to 301 μs and 3.0 μs, respectively. The former value appears to be much higher than that obtained from the lifetime measurement, indicating the presence of various energy transfer processes. The NIR spectrum of Pr3+/Ho3+-co-doped tellurite glass is dominated by strong Ho3+: 5I6 emission at around 1200 nm, being the result of the energy transfer from Pr3+ to Ho3+ ions. The shielding effectiveness of the prepared glasses showed good performance against high-energy photons. These findings suggest that the prepared glasses could be used in laser technology such as photodynamic therapy (PDT) treatment procedures and as shielding for radiation protection. [ABSTRACT FROM AUTHOR]

A series of the TeO2–GeO2–ZnO glass system was single and double doped with different Tb3+/Eu3+ ratios. Their luminescent and colorimetric properties were analyzed for possible use as phosphor materials in lighting devices. The characterization by X-ray diffraction and Raman spectroscopy verified the glassy nature of the fabricated samples. The luminescent properties of the doped glasses were analyzed by means of steady-state fluorescence and time-resolved spectroscopy. The Tb3+ excitation bands observed in the codoped samples while monitoring the 700 nm emission of Eu3+, as well as the shortening of Tb3+ lifetime in presence of europium indicated a Tb3+ → Eu3+ energy transfer, which main interaction type is electric dipole–dipole, according to Inokuti–Hirayama model. The Eu3+ → Tb3+ energy transfer also occurs in the samples but with lower efficiency. The CIE1931 chromaticity coordinates, upon different excitation wavelengths, show a multicolor tunning from green to orange-red due to the lanthanide concentration ratio and the Tb3+ → Eu3+ energy transfer process. [ABSTRACT FROM AUTHOR]

Investigation of the signal enhancement of Nd3+ codoped TeO 2 -ZnO pedestal waveguides, at 1064 nm, due to Au nanoparticles deposited over the core is presented for the first time. Nd3+ doped TeO 2 -ZnO thin film was obtained by RF Magnetron Sputtering deposition. The resulting core with 500 nm height and widths in the 4–40 μm range, exhibited low roughness average in all area measured (0.48 ± 0.04) nm. Minimum propagation losses of 2.2 dB/cm were observed for waveguide width of 40 μm whereas an increase took place for smaller ones. Scanning electron microscopy (SEM) allowed the waveguide structure inspection and transmission electronic microscopy (TEM) the Au nanoparticles evaluation. The results showed that the Au nanoparticles contributed up to 75 % of relative gain enhancement, under 808 nm excitation. This increase was due to the local field growth in the proximity of the nanoparticles that enhances the density of excited Nd3+. The internal gain that considers the propagation losses reached positive values for larger core widths (above 8 μm). The present study opens possibilities for optical amplifiers with low propagation losses based on different metal-dielectric composites, as well as other waveguide-based devices. • Enhanced optical gain in Nd3+ doped TeO 2 -ZnO waveguides due to Au nanoparticles. • New possibilities for integrated photonics assisted by plasmonics effects. • Au nanoparticles contribution: relative gain enhancement of up to 75 %, at 1064 nm. • Relative gain of about 12.0 dB/cm at 1064 nm: waveguide widths of 8, 6 and 40 μm. • Au nanoparticles influence: Nd3+ luminescence enhancement of 37 % (at 1.064 μm). [ABSTRACT FROM AUTHOR]

• Tellurite glasses doped with Er3+ and Au NPs were synthesized. • Heat treatment was applied to promote the growth of the Au NPs. • Coupling between Er3+ and Au NPs exert prominent enhancement in NIR emission. • Luminescence enhancement was improved under cooling conditions. • Semiempirical calculations explain the Er3+-Au NPs coupling. The plasmonic applications at low temperatures of metallic nanoparticles in glasses doped with rare-earth ions are not yet covered in-depth analysis in the literature. This paper insights into the coupling between gold nanoparticles and Er3+ embedded in tellurite glasses via luminescence enhancement of the emission centred at 1.53 µm under controlled temperature. This enhancement is obtained for the sample with 24 h of heat treatment (TErAu24) concerning the Er3+ single doped (TEr) at room temperature under 980 nm excitation. The enhancement remains under cooling conditions, consequence of the strong coupling between the plasmon and the Er3+, attributed to an increment of the localized plasmon mode volume at low temperatures. Further, the band area increment of the TErAu24 sample comparing the spectra at 98 and 348 K is 414 %, whereas for the TEr is about 348 %. These findings provide advanced understanding of the plasmonics on quantum emitters engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study investigates the glass-forming ability (GFA), structural, thermal, and optical properties of the TeO 2 –BaO–Bi 2 O 3 (TeBaBi) glass system, focusing on the mutual substitution trends of its constituent compounds. Prepared glasses were synthesized by the melt-quenching method at 900 °C and the GFA was extended by chemical compositions with lower TeO 2 (55–85 mol.%) and higher Bi 2 O 3 (5–15 mol.%) content via optimization of the synthesis process. The introduction of BaO and/or Bi 2 O 3 results in the increase of the glass transition temperature ( T g ≈ 327 – 384 ° C), molar volume (V g ≈ 28. 9 – 33. 1 cm 3 mol − 1) and optical basicity (OB ≈ 0.97–1.03). Prepared TeBaBi glasses exhibit satisfactory thermal stability and wide spectral region of optical transparency from 0.4–6.5 μ m with observed narrowing of optical window with higher TeO 2 content. Compositional evolution of T g may be described for the TeBaBi glasses using multilinear regression analysis with high correlation (r ≥ 0. 995) across the whole GFA region. The structure of studied TeBaBi glasses was investigated by Raman scattering and directly compared to the TeO 2 –ZnO–BaO (TZB) glass system prepared and characterized under identical conditions. Structural analysis revealed a similar degree of internal glass structure transformation regardless of whether a divalent zinc cation or trivalent bismuth cation is present. • Investigated TeO 2 –BaO–Bi 2 O 3 glass-forming ability (GFA), structure, thermal, and optical properties. • BaO/Bi 2 O 3 addition increased T g , molar volume, and optical basicity. • Compositional evolution of T g was described via multilinear regression across the whole GFA region. • Structural analysis via Raman scattering and comparison of TeBaBi and TeO 2 –ZnO–BaO glasses. • Observed similar degree of structure transformation regardless of whether a di/trivalent cation is present. [ABSTRACT FROM AUTHOR]

The present work focuses on the investigation of the properties of 33TeO 2 : 30B 2 O 3 : 30ZnO: 5BaO: 2Eu 2 O 3 glass prepared using microwave and conventional techniques. The prepared glasses were characterized by TGA/DSC analysis, density, refractive index, FTIR, XPS, absorption spectra, photoluminescence, lifetime, quantum efficiency, and X-ray-induced luminescence properties. The photoluminescence of the samples exhibited the strongest luminescence intensity of the Eu3+ ion at 614 nm (7F 2) under 394 nm excitation, resulting in a relatively high photoluminescence quantum yield of 39.64%. The luminescence decay time from the 5D 0 to 7F 2 level of glass prepared by the microwave technique is lower than that of a sample prepared by the conventional technique, with a luminescence decay time of 1.269 and 1.425 ms, respectively. X-ray-excited luminescence spectroscopy identified an emission peak at 614 nm in the samples, which can be attributed to 5D 0 -7F 2 transitions in the Eu3+ ion. These high-intensity samples were compared with bismuth germanate oxide (BGO) crystals used in radiation detection applications. From the various results examined, it is clear that the 33TeO 2 : 30B 2 O 3 : 30ZnO: 5BaO: 2Eu 2 O 3 glass prepared using the microwave technique is suitable for use as a scintillation material. • Microwave melting (MIC) yields glass with a higher proportion of NBO compared to conventional melting (MELT). • MIC glass exhibits the photoluminescence intensity higher than MELT glass 7 times. • The luminescence decay time of MELT glass is 1.425 ms and MIC glass is 1.269 ms. • The integral scintillation efficiency of MIC glass is 11.02% relative to the BGO crystal. [ABSTRACT FROM AUTHOR]

Featured Application: The study demonstrates the possibility of using terahertz pulses for measuring third-order nonlinear susceptibility responsible for electric-field-induced second harmonic generation. Third-order nonlinear susceptibilities χ 3 − 2 ω ; ω , ω , 0 and χ 3 − ω ; ω , − ω , ω responsible for electric-field-induced second harmonic generation and the optical Kerr effect were measured and directly compared for tellurite and chalcogenide glasses. The nonlinear coefficients were found by measuring the second harmonic radiation from samples under the action of an external field of terahertz pulses and by the classical z-scan technique, respectively. The influence of ambient air and helium gas on second harmonic generation was analyzed. It was demonstrated that both susceptibilities χ 3 − 2 ω ; ω , ω , 0 and χ 3 − ω ; ω , − ω , ω have close absolute values, which shows the dominant role of nonresonant electronic nonlinearity in the studied glasses. [ABSTRACT FROM AUTHOR]

The melt-quenching technique was used to synthesize tellurite glasses of the chemical composition 80TeO2-(20-x) ZnO-xV2O5. X-ray diffraction (XRD) patterns indicate the amorphous nature of the prepared glasses. Raman and FTIR measurements demonstrate a progressive substitution of the Te-O-Te linkages by the Te-O-V bridges and the formation of VO4 and VO5 units by a change of the vanadium coordination due to the higher number of oxygens incorporated by further addition of V2O5. The AC conductivity was investigated in the frequency range of 40 Hz to 107 Hz between 473 K to 573 K. A good coherence of the AC conductivity was found using a model correlating the barrier hopping (CPH) and the dominant conduction process changes from ionic to polaronic with the addition of V2O5. The dielectric constant exhibits high values in the range of lower and medium frequencies. Both variations of the electric modulus and the dielectric loss parameters with frequency and temperature showed a relaxation character mainly assigned to the vanadate phases. The electric modulus displays a non-Debye dielectric dispersion and a relaxation process. The present results open the door to future zinc-tellurite glasses-doped vanadium exploitation as a potential electrolyte-based material for solid-state batteries. [ABSTRACT FROM AUTHOR]

Structure-terahertz (THz) property relationship for sodium tungsten tellurite (NWT) and lanthanum tungsten tellurite (LWT) glass systems is reported and is the first of its kind for non-silicate oxide glasses. Raman spectroscopy was used to determine structural units, connectivity, and glass network. Terahertz time-domain spectroscopy (THz-TDS) was used to record the THz refractive index, n(THz), at 0.502 THz. NWT and LWT glasses record higher measurable n(THz) correlated to a glass network with substantial TeO2 and WO3 content with mixed Te–O–W linkages and TeO2- or WO3-rich content with homonuclear Te–O–Te or W–O–W linkages, respectively. Concurrent examination revealed three distinct regions of n(THz). [ABSTRACT FROM AUTHOR]

In analyzing the effect of alkali metal and alkaline earth metal oxide on the properties of tellurite glass, a series of tellurite glass samples doped with alkali metals and alkaline earth metals were prepared based on the TeO 2 -WO 3 -GdF 3 glass system by melt quenching method. Through tests and comprehensive analysis, the results show that after the F− ions successfully enter the glass network, the substitution of TeO 2 by alkali and alkaline earth metals could reduce the molar volume, which means the glass becomes more compacted. The influence on the glass network is mainly shown in [TeO 3 ] and [TeO 4 ] units. Alkali metals and alkaline earth metals could increase the asymmetry of the TWG: Eu3+ glass network, shorten the critical distance, and increase luminescence intensity by 8.6 times and improve color purity to 94%. In addition, alkali metals could prolong the fluorescence lifetime, while alkaline earth metals could shorten it. Te4+ [ABSTRACT FROM AUTHOR]

Rare earth doped barium tellurite glasses were synthesised and explored for their radiation shielding applications. All the samples showed good thermal stability with values varying between 101 °C and 135 °C based on dopants. Structural properties showed the dominance of matrix elements compared to rare earth dopants in forming the bridging and non-bridging atoms in the network. Bandgap values varied between 3.30 and 4.05 eV which was found to be monotonic with respective rare earth dopants indicating their modification effect in the network. Various radiation shielding parameters like linear attenuation coefficient, mean free path and half value layer were calculated and each showed the effect of doping. For all samples, LAC values decreased with increase in energy and is attributed to photoelectric mechanism. Thulium doped glasses showed the highest value of 1.18 cm−1 at 0.245 MeV for 2 mol.% doping, which decreased in the order of erbium, holmium and the base barium tellurite glass, while half value layer and mean free paths showed an opposite trend with least value for 2 mol.% thulium indicating that thulium doped samples are better attenuators compared to undoped and other rare earth doped samples. Studies indicate an increased level of thulium doping in barium tellurite glasses can lead to efficient shielding materials for high energy radiation.

The ternary TeO2–La2O3–WO3 glasses with a formula of (100 − y − x)TeO2–yLa2O3–xWO3 (y = 5 and 10 mol%; x = 10 to 25 mol%) were made by the melting and casting method for high Verdet constant diamagnetic magneto-optical (MO) materials in the application of MO devices operating at 1550 nm. The compositional effects of WO3 and La2O3 contents on key glass properties of thermal stability, Knoop hardness, optical transmission, and Verdet constant, were systematically studied for both series of glasses. High transparency level (T: >70 %) in the region from 0.4 to 5.2 μm and a high refractive index (n: 2.05 at 1550 nm) were obtained in the studied glasses. The tellurite glasses with 5 mol% of La2O3 exhibited higher thermal stability and refractive indices than those with 10 mol% La2O3. The 85TeO2–5La2O3–10WO3 glass exhibited a large Verdet constant value of 3.95 rad/(T·m) at 1550 nm among the studied glasses. These results show that the presented TeO2–La2O3–WO3 glasses have considerable potential as diamagnetic MO materials for MO device applications operating at 1550 nm.

Tellurite glasses are considered a potential alternative for applications not achieved by SiO2-based glasses, presenting interesting optical properties, such as high linear and nonlinear refractive indexes, extended optical window, being also suitable for metallic nanoparticle growth, like Te0. When doped with sulfide species, it can benefit the reduction of Te4+ to Te0, which can be advantageous to synthesize in-situ chalcogenide nanoparticles and quantum dots. This work presents investigations on the reduction of Te4+ to Te0 in tellurite glasses doped with PbS and PbO/ZnS, and aims to control this redox process through the processing with pulsed fs-laser. Tellurite glass samples were synthesized by melt-quenching technique and the thermal and structural properties were explored by different techniques, such as DSC, Raman scattering spectroscopy and mapping experiment, TEM and SAED. Reduction of tellurium to Te0 nanocrystals into tellurite glass after laser irradiation was studied in detail and confirmed by the presence of bands at ~120 and 140 cm−1 in Raman spectroscopy and mapping, assigned to the Te–Te vibrational modes, which suggest that S2− induces in-situ Te4+ reduction. Moreover, quasi spherical tellurium nanoparticles were observed through TEM and confirmed their chemical nature and crystallization by SAED. The study of tellurium reduction in the vitreous matrix becomes particularly important and promising for some applications, since its reduction generates changes in the refractive index by precipitation of Te0 nanoparticles, allowing the fabrication of waveguides and as photosensitive material for tridimensional data storage.

• Dy3+/Eu3+ dual doped tungstate-tellurite (TWKZBiDyEu) glasses synthesized. • Emitting colour tuned from white to orange-red with activator ion concentration. • Energy transfer from Dy3+ to Eu3+ ions confirmed via theoretical models. • TWKZBiDyEu glasses show good thermal stability with high activation energy. • In view of the above, glasses can be useful for w-LEDs and other photonic devices. In this study, dual ions (Dy3+/Eu3+) doped tungstate-tellurite (TWKZBi: Dy3+/Eu3+) glass matrices have been formed with the help of the melt quenching approach. The structural, thermal, morphological, and photoluminescent (PL) characteristics, as well as the energy transfer (ET) processes were thoroughly investigated. The structural features of the titled glasses have been explored via X-ray diffraction (XRD) analysis. The morphology and elemental studies of the titled glass matrices were verified with the help of field emission scanning electron microscopy (FE-SEM) along with energy dispersive spectroscopy (EDS). The PL results designate that the TWKZBi doped with Dy3+ ions glass samples exhibit a strong emission peak at 575 nm when excited via n-UV light, whereas Eu3+ doped TWKZBi glass sample demonstrates a conspicuous red emission band at 614 nm when stimulated with the n-UV light. In addition, TWKZBi glasses doped with both Dy3+ and Eu3+ ions demonstrate the emission peaks in the blue (B), yellow (Y) and red (R) zones of the electromagnetic spectrum. The combination of these peaks generates white and orange-red light through properly controlling the activator ion concentrations and selected excitations. Based on Dexter's and Reisfeld's approximation, dipole-dipole (d-d) interaction is responsible for the transfer of energy from donor (Dy3+) to accepter (Eu3+) ions. The decay profiles demonstrate the bi-exponential behaviour with a decline in the average lifetime (τ a v g) values as varying activator (Eu3+) ion concentrations in the titled TWKZBi: Dy3+/Eu3+ glasses. All the results above validate that the titled TWKZBi: Dy3+/Eu3+ glass samples could be fascinating for white LEDs and other optoelectronic applications. [ABSTRACT FROM AUTHOR]

We report a detailed numerical investigation of step-index tellurite fiber properties based on the careful experimental characterization of refractive indices for two tellurite-glass systems employed in fiber manufacturing. More specifically, our study focuses on two typical step-index configurations, namely weak and strong index differences between core and cladding glasses. We reveal that a wide range of dispersion-shifted features for tellurite fibers can be obtained in the 2–3 μm range combined with small or large effective mode areas. Our work also outlines the potential application of such dispersion-engineered fibers for nonlinear wavelength converters between near- and mid-infrared regions.

This work reported the radiation shielding characteristic of the bismuth titanium vanadium sodium tellurite glass system. The density of the specially-developed glass samples was increased from 2.21 to 4.01 g/cm3 with the addition of Bi2O3, despite the fact the molar volume is decease within 85.43–54.79 cm3/mol. The WinXcom program was used to approximate the effect of Bi2O3 on the gamma radiation shielding parameters of bismuth titanium vanadium sodium tellurite glasses. The μm values decrease with the increase of Bi2O3 concentration. The computed data shows that the glass sample with 20 mol.% of Bi2O3 content has the greatest radiation attenuation performance in comparison to other selected glasses. The Bi2O3–TiO2–V2O5–Na2O–TeO2 glass system shows excellent neutron shielding material with high long-term light transmittance and discharge resistance and could be potentially used as transparent radiation-resistant shielding glass applications.

The first systematic study of linear and non-linear optical, magneto-optical and structural properties of pure TeO 2 glass is presented with regard to different synthesis and material processing conditions. Prepared glasses were synthesized by the intermittent quenching from 900 ∘C in platinum or alumina crucibles and characterized prior to and after optical polishing. The position of the long-wavelength/phonon absorption edge was investigated using various optical models and experimentally obtained data of refractive index and Verdet constants were used for the estimation of magneto-optical anomaly parameter. During synthesis in alumina crucible, up to about 11 wt.% of Al 2 O 3 incorporates into the glass (verified by EDS/XRF and Raman/FTIR spectroscopy) partially transforming the original pure TeO 2 glass backbone structure composed of [TeO 4 ] trigonal bipyramids to [TeO 3+1 ] and [TeO 3 ] structural units with the expected integration of Al into Te−O−Al bridges. The presence of Al 2 O 3 results in lowered density ρ (5.60 → 4.72 g cm−3), refractive index n 1550 (2.086 → 1.927) and Verdet constant V 632 (36.3 → 21.9 rad T−1 m−1) and in increased optical-band-gap energy E g (3.69 → 3.72 eV) and Abbe number ν D (19.9 → 26.9) compared to pure TeO 2 glass prepared in platinum crucible. A dataset of the obtained complex optical parameters (refractive index and extinction coefficient) in the wide spectral range of 193 − 11000 nm is included in the supplementary part. • Pure TeO 2 glass: First complex study of optical and magneto-optical properties. • Impact of synthesis in alumina and Pt crucible on resulting glass properties. • Effect of polishing-induced modifications on optical properties. • Optical (n , k) and magneto-optical (V) constants determined in a broad spectral region. • Estimation of band-gap-energy E g , magneto-optical anomaly (γ) and long-wavelength/phonon edge. [ABSTRACT FROM AUTHOR]

Rare-earth-doped glasses have garnered significant interest in photonics and optical communication due to their unique luminescent properties. Nevertheless, is important to understand what means low content of Er 3 + ions in germanate-tellurite glasses, since when there are few Er 3 + ions in a glass matrix, these ions could be approximated with quantum emitters. The existing literature predominantly focuses on high doping concentrations of Er 3 + ions in glasses, overlooking the subtleties and advantages associated with low doping contents. This research addresses this gap by exploring the optical and structural properties in germanate-tellurite glasses doped with low concentrations of Er 3 + ions. Optical spectroscopy techniques were employed to characterize the luminescent properties and additionally, structural analysis was conducted to understand the glass structure as a function of Er 3 + ions content. Our comprehensive analysis of the optical and structural properties of low Er 3 + -doped glasses provides a foundation for further exploration in the field of photonics, optical communications and plasmonics. • XRD analysis confirmed the amorphous nature of the glasses, while FTIR revealed the presence of functional groups on the glass surface and low OH- concentration in the glass structure. • Raman spectroscopy revealed changes in the energy of the phonons. The influence of increased Er 3 + doping on NBO generation was reported, indicating a modification in the glassy matrix due to the presence of Er 3 + ions. Besides, the observed high linear and nonlinear refractive index values suggest potential applications in nonlinear optics. • Er 3 + doping was further confirmed by absorption bands corresponding to electronic transitions in the UV–VIS–NIR region. The Tauc-Meth model was employed to calculate direct and indirect energy gaps, revealing an increase in Urbach energy with increasing Er 3 + concentration, indicative of enhanced structural disorder within the glasses. • When excited with 980 nm light, three distinct bands were observed in the up-conversion emission spectra at 520 nm, 550 nm, and 660 nm. These bands correspond to energy level transitions in Er 3 + ions. • Notably, green emission (around 520 nm and 550 nm) was strongest in all samples. In contrast, red emission (660 nm) was consistently weaker. These findings indicate that the germanate-tellurite glass composition favors emitting green light over red light through up-conversion. Additionally, exciting the material with 980 nm light also resulted in near-infrared (NIR) emission centered at 1530 nm. [ABSTRACT FROM AUTHOR]

• Er 2 O 3 content increment affects the structure, density, molar volume, and OPD. • The intensity of Er3+ green and infrared emissions peaked at 1% mol and 4% mol of Er 2 O 3 , respectively. • The measured lifetime values (547 nm transition) surpassed those previously reported for TZL glasses. • Up-conversion was monitored at 808 and 975 nm excitation from 50 to 1090 mW. • ESA and ETU processes operate simultaneously in the up-conversion mechanism. The effect of Er 2 O 3 concentration on the structural, physical, and spectroscopical properties of (70- x)TeO 2 -20ZnO-10Li 2 O-xEr 2 O 3 glasses (x = 0.1–4 mol %) was studied by X-ray diffraction (XRD), Energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FT-IR), density measurements, optical absorption, photoluminescence, and time-resolved spectroscopic techniques. All glasses are amorphous, as observed by XRD. FT-IR showed changes in the non-bonding oxygens band, and EDS detected aluminum from crucible leaching, which influenced the physical properties. According to optical absorption spectra, the doped glasses are more UV transparent than the glass matrix. Photoluminescence was characterized first under a UV excitation wavelength, determining the time decay and Er3+→Er3+ energy transfer mechanisms by monitoring the 2H 11/2 →4I 15/2 and 4S 3/2 →4I 15/2 transitions. The up-conversion process was monitored using two CW lasers with wavelengths of 808 and 975 nm, varying the power in a wide range, and it was determined that the two-photon process dominates the anti-stokes emission mechanism. [ABSTRACT FROM AUTHOR]

In the TeO 2 -WO 3 -GdF 3 glass system, 42 different proportions of glass have been prepared, showing the ideal forming area. The influence of proportions on the density was measured and several devitrified samples were analyzed by XRD. Discussed the internal structure changes and the variation of component concentration by Raman and Fourier transform infrared spectra. The properties and structural features of glasses were analyzed in terms of molar volume. TeO 2 and WO 3 act as glasses former while GdF 3 act as a modifier which forms mixed linkages Te–O–W, Te–F–W, etc. UV–Vis spectra were recorded to determine optical absorption/transmission and energy gap values. These results suggest that the TeO 2 -WO 3 -GdF 3 glass system could be potentially used as photonic devices and basic materials. [ABSTRACT FROM AUTHOR]

In the presented work, the tellurite glasses TeO2-WO3-ZnO doped with Tm3+ and Ho3+ ions were prepared by the same glass forming method. X-ray diffraction (XRD) and differential thermal analysis (DTA) techniques were used to study the effects of the forming technology on the thermal and structural properties of the fabricated glasses. After controlled crystallization of investigated glasses, the emission in the VIS- and NIR range was determined. The effect of silver doping on emission intensity was investigated. The value of the activation energy of the glass crystallization process was determined, while the Ea value for pure TeO2 glass was much lower than for tellurite glasses TeO2-WO3-ZnO. [ABSTRACT FROM AUTHOR]

The synthesized glass system with a composition of (80-x) TeO2-10P2O5-10Nb2O5-xKCl mol% (where x = 5, 10, 15, 20, and 25) was successfully fabricated. The density (ρ) and molar volume (Vm) have been calculated. The investigated glasses were characterized using different analysis methods (differential thermal analysis (DTA) and UV-VIS-NIR spectroscopy). The radiation shielding effectiveness of the synthesized glass system was evaluated using different shielding parameters, such as mass and linear attenuation coefficients (MAC, LAC), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), and effective electron number (Neff). The results showed that with the increasing potassium chloride (KCl) concentration and decreasing tellurium oxide (TeO2) concentration, the density, refractive index, Urbach energy (Eu), and glass transition temperature (Tg) decreased, while the optical energy gap (Eopt) and thermal stability increased. As the KCl concentration increases, the values of MAC, LAC, and Zeff increase in the following order: TPNK5 % > TPNK10 % > TPNK15 % > TPNK20 % > TPNK25 %. Additionally, the shielding effectiveness of TPNK glass system showed good performance compared with some standard materials. The synthesized glass with a minimum KCl content has both good shielding effectiveness and good optical properties, in addition to reasonable thermal stability, which makes it suitable for shielding and optical applications. [ABSTRACT FROM AUTHOR]

The enhancement of trivalent europium ion on the spectroscopic properties of zinc barium tellurite oxyfluoride glasses has been investigated set up under 8 different conditions of the (55-x)TeO2-10ZnF2-35BaO-xEu2O3 with 0.0 ≤ x ≤ 8.0 (in mol %). The physical, optical and photoluminescence properties. Measuring the UV-VIS-NIR absorption spectra with a proven measured in air atmosphere in the range of 200–2,500 nm demonstrated an extension of intensity of all absorption bands with Eu2O3 contents increased. In addition, the performance with excitation wavelengths of 465 nm carried out the photoluminescence properties of Eu3+ doped ZnF2-BaO-TeO2 glass system. As a final observation, five photoluminescence bands were monitored at 578 nm, 591 nm, 612 nm, 652 nm and 700 nm that transition from the relaxation of an electron from excited state to lower state. The intense peak (reddish-orange emission) of the glasses was found at 612 nm. Methodical analysis of the results encouraged that the Eu2O3 doped is applicable for laser material and optical device applications. [ABSTRACT FROM AUTHOR]

To increase the emission intensity of Pr SP 3+ sp ions, Yb SP 3+ sp ions appear as an efficient sensitizer [[13]]. Due to a non-exponential character of the decay data, we have determined the experimental lifetime as being equal to the effective lifetime defined as HT ht Graph (4) Graph: Fig. [[36]]) HT ht Graph (5)where I i SB Pr-Yb sb and I i SB Pr sb are the effective lifetimes with and without Yb SP 3+ sp -coping, respectively, but for the same concentration of Pr SP 3+ sp ions. Emission spectra Emission spectra of Ln-doped samples TPr and TPrYb were measured in the same conditions allowing one to compare their relative intensities; additionally, in order to demonstrate the effect of the Pr SP 3+ sp ion concentration ( I N i SB Pr sb ; see Table 1) on the emission spectra, the PL signal of both samples (in arbitrary units) has been divided by I N i SB Pr sb . [Extracted from the article]

We report the symmetry of mechanical and gamma-ray attenuation properties for some tellurite glasses through elastic moduli, mechanical, and transmission properties as a function of varied WO3 amount in glass configuration. Four glass samples, along with different molar compositions as well as WO3/GdF3 substitution ratios, are investigated. Transmission properties using several essential parameters, such as attenuation coefficients, half-value layers, effective atomic numbers, effective conductivity, and buildup factors, are calculated in the 0.015–15 MeV energy range. Moreover, elastic moduli and Poisson’s ratios (σ) of the studied glass are calculated using the Makishima–Mackenzie model. The M4 sample with the highest WO3 addition is found with superior photon attenuation properties among the glasses investigated. Poisson’s ratio (σ) is increased, while all elastic moduli are decreased. Young’s modulus is reported as 62.23 GPa and 36.45.37 GPa at the highest and lowest WO3 mol%, respectively. It can be concluded that WO3 is a functional and monotonic tool in ternary-tellurite glasses for multiple modifications and enhancement purposes on gamma-ray attenuation, elastic moduli, and mechanical properties. It can also be concluded that increasing the WO3 amount in tellurite glasses may be considered a tool in terms of providing symmetry for mechanical and gamma-ray attenuation properties.

High real‐space resolution neutron diffraction measurements up to 34 Å−1 were performed on a series of xCuO–(100 − x)TeO2 (x = 30, 40 and 50 mol%) glasses that were synthesized by the melt‐quenching technique. The Fourier transformation of neutron diffraction structure factors was used to generate the pair distribution functions, with the first peak at 1.90 Å due to the overlapping Te–O and Cu–O atomic pairs. Reverse Monte Carlo (RMC) simulations were performed on the structure factors and the six partial atomic pair distributions of Cu–Cu, Cu–Te, Cu–O, Te–Te, Te–O and O–O were calculated. The Te–O and Cu–O distributions are very similar and asymmetrical, which revealed that there is a significant short‐range disorder in the tellurite network due to the existence of a wide range of Te—O and Cu—O bond lengths. A high‐Q (magnitude of momentum transfer function) neutron diffraction study revealed that the average Te–O coordination number decreases steadily from 3.45 to 3.18 with an increase in CuO concentration from 30 to 50 mol% in the glass network. Similar coordination number modifications were earlier found by the RMC analysis of neutron diffraction data sets of copper tellurite glasses that were performed up to lower Q maximum values of 9.5 Å−1. The comparison of high‐Q and low‐Q neutron diffraction studies reveals that RMC is a powerful and possibly the only technique that is available to elucidate the glass short‐range and medium‐range structural properties when diffraction data are available up to low Q values of, say, 9.5 Å−1, and when cation–oxygen bond lengths are strongly overlapping and cannot be resolved by Fourier transformation. In situ high‐temperature (473 K) neutron diffraction studies of 50CuO–50TeO2 glass revealed that significant distortion of the tellurite network occurs with heating. [ABSTRACT FROM AUTHOR]