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Shielding glass materials doped with heavy metal oxides show an improvement in the effectiveness of the materials used in radiation shielding. In this work, the photon shielding parameters of six tellurite glass systems doped with several metal oxides namely, 70TeO2-10P2O5- 10ZnO- 5.0PbF2- 0.0024Er2O3- 5.0X (where X represents different doped metail oxides namely, Nb2O5, TiO2, WO3, PbO, Bi2O3, and CdO) in a broad energy spectrum, ranging from 0.015 MeV to 15 MeV, were evaluated. The shielding parameters were calculated using the online software Phy-X/PSD. The highest linear and mass attenuation coefficients recorded were obtaibed from the samples containing bismuth oxide (Bi2O3), and the lowest half-value layer and mean free path were recorded among the other samples. Furthermore, the shielding effectiveness of tellurite glass systems was compared with commercial shielding materials (RS-369, RS-253 G18, chromite, ferrite, magnetite, and barite). The optical parameters viz, dispersion energy, single-oscillator energy, molar refraction, electronic polarizability, non-linear refractive indices, n2, and third-order susceptibility were measured and reported at a different wavelength. Bi2O3 has a strong effect on enhancing the optical and shielding properties. The outcome of this study suggests the potential of using the proposed glass samples as radiation-shielding materials for a broad range of imaging and therapeutic applications.

Novel series of fluorotellurite lithium niobate glasses with compositions TeO2–LiNbO3–BaO–BaF2–La2O3 coded as Pr3, Pr4, Pr5, Pr6, and Pr7 were fabricated using the traditional process of quenching the melt. The density of the fabricated glasses was varied from 5.1689 to 5.4088 g/cm3, while optical packing density (o.p.d) was taken values from 50.85 to 64.4 g atom l−1. The thermal features glasses were determined by using (DSC), while their optical properties were determined in ultraviolet–visible–near-IR (UV–Vis–NIR) spectral region. Results revealed that the glass transition temperature (Tg) has the lowest value for Pr6 glass sample otherwise the highest value in Pr3 sample. The thermal stability (ΔT) was equal to 133, 149,154,127, and 153 °C for Pr3, Pr4, Pr5. Pr6, and Pr7 glass samples, respectively. The optical energy gap (Eopt) varied from 2.81 to 3.12 eV, while the Sellmeier gap energy (ES) changed from 6.6 to 8.55 eV. Also, gamma-ray shielding competences of the fabricated glasses were evaluated in terms of their mass and linear attenuation coefficients (MAC, LAC), half-value layer (HVL), and mean free path (MFP). The obtained values showed that LAC was in the order of Pr7 > Pr6 > Pr3 > P4 > Pr5, while HVL arranged in the order of Pr7

This research reported on the radiation safety characteristics of doped fluorophosphate glasses with heavy rare earth lanthanide (Sm2O3) in the composition 40P2O5/30ZnO/20BaF2/3.8K2TeO3/1.2Al2O3/5.0Nb2O5/30000 ppm Sm2O3 and 40P2O5/30ZnO/20BaF2/3.8K2TeO3/1.2Al2O3/5.0Nb2O5/40000 ppm Sm2O3 in mol%. The parameters for shielding like that mass attenuation coefficient, MAC, linear attenuation coefficient, LAC, tenth value layers, TVL, half-value layers, HVL, effective atomic number, (Zeff), mean free path, MFP, electron density, Neff, electronic cross-sections, ECS, and total atomic cross-sections, ACS, were calculated between 0.015 and 15 MB of preparation glasses. The protection parameters of the current glasses are good in comparison to industrial materials used for nuclear shieldings, such as glass RS 253, ordinary concrete (OC), hematite serpenite (HS), or basalt magnet (BM). From the above mention results, the prepared glasses can be used as radiation safety materials.

Luminescent phosphate glasses having the composition 40P2O5-30ZnO-20BaF2-3.8K2TeO3-1.2Al2O3-5Nb2O5 in mol.% doped with 3 × 103 ppm and 4 × 103 ppm Sm2O3 were successfully prepared by a melt-quenching technique. The investigated glasses were characterized by x-ray diffraction, UV–visible–NIR, absorption, emission, and fluorescence lifetime analysis. The radiative properties were calculated using Judd–Ofelt (J–O) spectral intensity parameters for each of the glasses, which revealed the following trend: Ω2 > Ω4 > Ω6. The J–O intensity parameters were used to evaluate the spontaneous emission properties including branching ratios, transition probabilities, and radiative lifetime. The value of the optical energy band gap was found to decrease with an increase in Sm3+ content, which is explained on the basis of structural changes. The calculated stimulated emission cross-section $$ \sigma_{\rm{SE}} , $$ at 1.62 μm of glasses studied was high, and increased from 3.81 × 10−21 cm2 to 4.38 × 10−21 cm2 with increasing Sm3+ ion concentration. The structure of the glasses was investigated by computing $$ {\hbox{Internuclear }}\,\left( {r_{\rm{i}} } \right) $$ , Polaron radius $$ \left( {r_{\rm{p}} } \right) $$ and field strength $$ \left( F \right) $$ and measurement of Raman spectra.

A systematic characterization of optical and chemical properties of fluorotellurite glasses based on 70TeO2-5 M x O y -10P2O5-10ZnO-5PbF2 glasses as function of alkaline earth metals as network modifiers were studied and analysed. The Z-scan results show that all the compounds have NLO properties such as nonlinear refractive index ( n 2 ) and two photon absorption ( β ). Finally, using ( n 2 ) and ( β ) we also determined the third-order nonlinear optical susceptibility χ 〈 3 〉 . It was found that the alkaline earth metals elements, have an influence on such NLO properties. Based on the ability of the lattice modifiers to decrease the band-gap energy while simultaneously increasing the linear refractive index of the TeO2-based glass, we investigated how these modifiers affect the non-linear refractive index.

In this paper an attempt was made to investigate the compositional, microstructural, thermal and optical properties of 40P2O5- 30ZnO- 20BaF2- 3.8K2TeO3- 1.2Al2O3- 5Nb2O5- 30,000 ppm Er2O3 (PZBKTANEr) novel glasses fabricated by the melt quench technique. The amorphous nature of the glasses was confirmed by X-ray diffraction studies. We estimated the glass transition temperature and thermal stability against the crystallization of present glasses by using differential thermal analysis (DTA). The results of the differential thermal analysis (DTA) indicate that (PZBKTANEr) glasses have a high thermal stability and low tendency to crystallization.The optical absorption edge has been evaluated within the Urbach approach by using UV–vis-NIR spectroscopy. Moreover, the Judd– Ofelt parameters Ω2, Ω4 and Ω6 the oscillator strength type transition probabilities, spectroscopic quality factors, branching ratios and radiative lifetimes of several excited states of Er3+ have been evaluated. The classical Mc Cumber theory was used to evaluate the emission cross-sections for the 4I15/2 → 4I13/2 transition at a wavelength of around 1.54 μm. Gain cross-section for the Er3+ laser transition 4I15/2 → 4I13/2 was obtained. The effective emission cross section bandwidth FWHM (75.924 nm) and height stimulated emission cross-section (5.5 × 10−21 cm−2) of present glasses were reported. Hence the thermal and spectroscopic properties indicate that this glass doped with Er3+ can be used for application of the optical device. Furthermore the structure of this glass was analyzed by Raman spectroscopy.

BACKGROUND: Metal oxide glass composites have attracted huge interest as promising shielding materials to replace toxic, heavy, and costly conventional shielding materials. OBJECTIVE: In this work, we evaluate shielding effectiveness of four novel tellurite-based glasses samples doped with oxide metals (namely, A, B, C, and D, which are 75TeO2- 10P2O5- 10ZnO- 5PbF2- 0.24Er2O3 ; 70TeO2- 10P2O5- 10ZnO- 5PbF2 -5MgO- 0.24Er2O3; 70TeO2- 10P2O5- 10ZnO- 5PbF2- 5BaO- 0.24Er2O3 ; and 70TeO2- 10P2O5-10ZnO- 5PbF2- 5SrO; respectively) by assessing them through a wide range of ionizing radiation energies (0.015–15 MeV). METHODS: The radiation-shielding parameters including mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half-value layer (HVL), mean free path, (MFP), effective atomic number (Zeff), effective electron number (Neff), and the transmission factor are computed in the selected range of ionizing radiation energies. Furthermore, the proposed samples were compared with the most common shielding glass materials. The optical parameters viz oscillator, dispersion energy, nonlinear refractive indices, molar, and electronic polarizability of these transparent glasses are reported at different wavelengths. RESULTS: The results show that the proposed samples have considerable effectiveness as transparent shielding glass materials at various ionizing radiation energies. They can be employed for effective radiation-protection outcomes. Sample C demonstrated slightly better shielding properties than the other samples with differences of 1.33%, 4.6%, and 4.2% for samples A, B, and D, respectively. A similar trend is observed regarding the mass attenuation coefficients. Nevertheless, sample B shows better optical properties than the other prepared glass samples. CONCLUSIONS: Our findings indicate that the proposed novel glass samples have good shielding properties and optical characteristics, which can pave the way for their utilization as transparent radiation-shielding materials in medical and industrial applications.

Tellurite glass with composition 90TeO2-10Nb2O5-10ZnO in mol% codoped with x(Tm2O3/Dy2O3), where x = 10,000, 20,000 and 30,000 ppm were prepared by quenching melting technique. The optical density and photoluminescence properties of this glass were studied. Spectroscopic parameters such as the absorption cross section, σab(λ), emission cross section, σem(λ), effective band width, (Δλ), internal gain coefficient, gR(λ), and the chromaticity coordinates CIE of the emitted light for this glass were computed. The, ( σ e m ) , (Δλ), and σg(λ) parameters increase from 5.95 × 10−21 to 8.86 × 10−21 cm2, from 123 to 127 nm and from 4.2 to 6.3 dB/cm, respectively when increasing Tm3+/Dy3+ ions from 10,000 to 30,000 ppm in the host glass matrix. Compared the luminescence intensity and spectroscopic parameters in these glasses are greatly enhanced. From CIE results indicate that the emission color varied from blue to white can be achieved by tuning Tm3+/Dy3+ ratio under excitation at 466 nm. The present glasses are found to be a suitable candidate for solid state laser material.

We have investigated the optical and spectroscopic properties of new Er 3+ -doped fluorotellurite glasses with the basic molar composition 75%TeO 2 -10%P 2 O 5 -10%ZnO-5%PbF 2 , modified by replacing 5%TeO 2 by four various metal oxides, namely MgO, PbO, SrO and CdO. The ellipsometric data have provided a Sellmeier-type dispersion relation of the refractive index of the investigated glasses. The optical absorption edge has been described within the Urbach approach, while the absorption and fluorescence spectra have been analyzed in terms of the standard Judd–Ofelt theory along with the photoluminescence decay of the 4 I 13/2 and 4 S 3/2 levels of the Er 3+ ion. The absorption and emission spectra of the 4 I 15/2 ↔ 4 I 13/2 infrared transition have been analyzed within the McCumber theory to yield the peak emission cross-section and figure of merit (FOM) for the amplifier gain. It appears that the glass containing MgO as a modifier is characterized by the largest FOM suggesting that the fluorotellurite matrix with this oxide can be a good novel host for Er 3+ ion doping. Finally, we propose a new simple method to calculate the mean transition energy of the McCumber approach as the arithmetic average of the barycenter wavenumbers of absorption and emission spectra.

The luminescent oxide glasses with composition 50P2O5- 30ZnO- 20CdO (PZCdO pure) and 50P2O5- 30ZnO- 20CdO- 30000 ppm Tm2O3 (PZCdO:Tm) were synthesized by using melt- quenching technique. The optical energy gap and Urbach energy of these glasses were calculated by using UV–Vis–NIR spectroscopy. Judd– Ofelt parameters Ω2, Ω4 and Ω6, branching ratio, βR, and radiative lifetimes, τR, of Tm3+ ions doped PZCdO glasses were estimated. The spectroscopic results showed that the present glasses has the effective emission cross section bandwidth (Δλeff = 90 nm) and high stimulated emission cross-section (σem = 1.5 × 10−21 cm2). The blue up conversion emissions sharp band at 458 nm corresponding to transition 1D2 → 3F6 and weak emission band in NIR region assigned to 1G4→3H4 for the glasses PZCdO:Tm with UV- excited at 354 nm region were obtained. From result we can suggest that the present glasses can be used for blue light emitting diodes BLED chip.

Novel fluorotellurite glasses with composition 70TeO2·5MxOy·10P2O5·10ZnO·5PbF2 (mol %) containing 600 ppm Er2O3, where MxOy = (MgO, PbO, Bi2O3, Nb2O5, TiO2, BaO, WO3, SrO, CdO) have been prepared using the conventional melt-quenching method. Studies of the nonlinear optical refractive index and photoinduced piezooptics were carried out. The Mid-Infrared spectroscopy, optical transmission, photoluminescence and photoinduced changes of diagonal piezooptics and nonlinear optics refractive indices coefficient measurements were applied to determine the appropriate glass modifier to achieve the desirable optical properties and high performance. The glasses may be useful for operation by high-intensity laser pulses.

We have investigated the thermal and spectroscopic properties of Er3+-doped fluorotellurite glass with the basic molar composition 75%TeO2–10%P2O5–10%ZnO–5%PbF2 and the glasses modified by substituting 5%TeO2 by a metal oxide, namely TiO2 or BaO. As follows from the thermal studies, the glass containing TiO2 as a modifier exhibits a higher stability against crystallization with respect to two other glasses. The ellipsometric data have provided a Sellmeier-type dispersion relation of the refractive index of the investigated glasses. The absorption and fluorescence spectra, along with the photoluminescence decay of the 4I13/2 levels of the Er3+ ion, have been analyzed within the Judd–Ofelt and Fuchtbauer-Ladenburg approaches. It appears that the quantum efficiency of the 4I13/2 → 4I15/2 transition is quite high (above 70%), being the highest (97%) for the glass containing TiO2 as a modifier. The absorption and emission cross-section results for the 4I15/2 ↔ 4I13/2 transition show that the glass containing TiO2 is characterized by the largest figure of merit (FOM) for the amplifier gain and indicate this matrix as a promising new host for doping with rare-earth ions.

Er3+ ions doped TeO2 based glasses were prepared by quenching melting technique. A systematic characterization of glass transition temperature and optical properties of the prepared glass was carried out. The gain cross-section for the Er3+laser transition 4I13/2→4I15/2 was calculated. The results show the TNBZ glass doped with 2000 ppm of Er2O3 had the maximum value of gain cross-section equal to 14.4 cm−1 and large stimulated emission cross-section (1.4×10−20 cm2). The glasses developed here showed the widest bandwidths of gain cross section from 249 to 1106 cm−1. Moreover the Raman gain coefficient of the present glass was obtained from Raman scattering experiments using 532 nm excitation. This composition has also the maximum value of Raman gain coefficient (g=1.4×10−10 m/W) and it has the highest value of full width half maximum (FWHM≈ 380 cm−1). Finally, the structure of the prepared glasses was investigated through deconvolution Raman spectra. The thermal stability and spectroscopic properties indicate that this glass doped with Er3+ is a promising candidate for fiber lasers and Raman gain amplifiers.

We have investigated the thermal and spectroscopic properties of Pr3+-doped new tellurite matrix with the molar composition 60%TeO2–27%WO3–10%PbO–3%Lu2O3 (TWPLu). The differential thermal analysis has shown that addition of Lu2O3 to the glass results in an increasing resistance against crystallization. The ellipsometric data have provided a Sellmeier-type dispersion relations of the refractive index of the investigated glasses. The optical absorption edge of the TWPLu matrix has been described within the Urbach approach, while the absorption and fluorescence spectra of the Pr3+-doped TWPLu glasses have been analyzed in terms of the standard Judd–Ofelt theory along with the luminescence decay of the 3P0 and 1D2 levels of the Pr3+ ion. A significant influence of the Pr3+ ion concentration on the photoluminescence intensity as well as on decrease of the lifetimes of both levels has been explained by a non-radiative energy transfer between the ions through cross-relaxation and energy migration processes.

The behavior of a silver electrode contacting Ce0.8Sm0.2O1.9 (samaria-doped ceria or SDC) electrolyte under external cathodic polarization in the temperature range 350–700 °C was examined by means of long-term polarization experiments, scanning electron microscopy, and electrochemical impedance spectroscopy. A silver deposit is formed around the silver cathode via a surface migration mechanism without the occurrence of the gas-phase transport phenomenon during polarization. This results in an increase in both the electrode-electrolyte contact area and the triple-phase boundary length, which in turn causes decreases in charge transfer resistance and electrolyte resistance.

It is reported that there is substantial enhancement of the optical second harmonic generation (SHG) at 1064 nm Nd:YAG laser wavelength for LiB3O5 nanocrystatllites embedded into the electric field aligned photopolymer oligoetheracrylate matrices. The borate nanocomposite was put between the electrodes containing Ag/ZnO NP with silver sizes 20, 40 and 60 nm. We study an influence of the Ag NP sizes on the output SHG. It is clearly seen that only excitation by the green continuous wave 532 nm laser with power about 350–400 mW with beam diameter about 4 mm give significant effect. The latter confirms a principal role of the surface plasmon resonances spectrally overlapped with the nonlinear excitations responsible for the observed changes of the SHG.

Multicomponent telluride-tungstate glasses containing Nd 3+ and Er 3+ ions were studied experimentally at 77 and 293 K using spectroscopic methods. The Judd–Ofelt intensity parameters were derived from the absorption spectra and used to calculate the radiative lifetimes and branching ratios. The quantum efficiency η = 0.95 of the 4 F 3/2 level of Nd 3+ ion is higher than the typical value of other tellurite-based glasses. For low concentration of Er 3+ ions, the luminescence decay of the 4 S 3/2 and 4 I 11/2 levels is governed by radiative transitions and multiphonon relaxation involving the Te-O highest energy vibrations.

In this paper, optical glass nanocomposites (nanoparticles sizes up to 100 nm) with composition TeO 2 –WO 3 –PbO–xEr 2 O 3 –yPr 6 O 11 (x = 0.30 mol%, y = 0.70 mol%) embedded into polymer matrices was reported. The two types of polymers chosen for present study were: photopolymer oligoetheracryalte (OEA) and polymethylmethacrylate (PMMA), respectively. The incorporation of the titled nanoparticles into the polymer matrices is analyzed optically. The fluorescence spectra of the nanocomposites were compared with the fluorescence spectra of bulk glasses. Based on the comparison of Er 3 + and Pr 3 + ions' energy level schemes, possible energy transfer processes were identified. The prepared glasses are promising candidates for the white light emitting diodes applications.

The paper presents a simple fabrication method of porous silica xerogel films. By adding a surface active agent Triton X-100™ to the starting solution, we can considerably reduce the surface tension, which, in turn, allows to fabricate silica films of high porosity. The paper presents the influence of surfactant content and the influence of heating temperature on the refractive index and thickness of the fabricated films. We fabricated silica films of the minimum refractive index below 1.3 and corresponding porosity ∼50%. Due to low refractive index, the elaborated porous silica xerogel films can be applied to reduce the light reflection coefficient in optical systems. In this work the spectral characteristics of the refractive index, extinction coefficients, the reflection and transmission coefficients and also depolarization factor are presented. The paper also provides results of surface morphology of produced layers, obtained using an atomic force microscope.

The glass samples with composition TeO2–WO3–PbO–xEr2O3–yPr6O11 (x = 0,30%mol, y = 0,07%mol) were synthesized and studied with respect to the light emitting features. These glasses possess high photothermal stability and resistance against crystallization during reheating. The observed fluorescent spectra cover a wide visible spectral range. Due to simultaneous presence of both Er3+ and Pr3+ ions in the glass, nearly all absorption peaks are strongly overlapping. Careful analysis of the emission spectra allowed to assign all the observed peaks. From comparison of the Er3+ and Pr3+ ions’ energy level schemes, possible energy transfer processes were identified. The prepared glasses possess high quantum efficiency, which allow use them for white light emitting diodes.