Structural and Optical Behavior of Vanadate-Tellurate Glasses Containing PbO or Sm2O3 (original) (raw)
Spectroscopic Properties of Rare Earth Ion Doped TeO2-B2O3-PbO Glass
Jurnal Teknologi, 2014
This work focuses on the spectroscopic study of RE3+ ion, namely, trivalent neodymium (Nd3+) doped lead borotellurite glass with a composition of TeO2-B2O3-PbO. The glass sample has been prepared by conventional melt-quenching technique. The density, molar volume and optical energy band gap of these glasses have been measured. The refractive index, molar refraction and polarizability of oxide ion have been calculated by using Lorentz-Lorentz relations. The absorption spectra are recorded using UV-Vis-NIR spectrometer in the range of 200-900 nm.
Influence of Rare Earth Ions on the Optical Properties of Tellurite Glass
Acta Physica Polonica A, 2011
The goal of this work was to investigate the influence of rare-earth ions such as Nd 3+ and Er 3+ on the optical properties of tellurite glass of the TeO2-WO3-PbO-La2O3 system. The optical studies of the glasses comprised spectrophotometry (reflectance and transmittance) and spectroscopic ellipsometry. The spectrophotometric measurements yield a number of narrow absorption bands which correspond to characteristic transitions between the ground-and consecutive excited states of rare-earth ions. From ellipsometric studies, in turn, the dispersion of the refraction coefficient has been obtained which appears to be practically the same for the tellurite glass matrix and the matrix doped with Nd 3+ and Er 3+ ions.
Structural, Thermal and Optical Properties of Rare Earth Doped Lead-Tellurite Oxide Glasses
2021
Structural, thermal and optical properties of lead-tellurite oxide glasses consisting TeO2 – PbO – Bi2O3 – Er2O3, synthesized by high temperature melt-quenching-thermal annealing method were investigated in this study. The role of rare-earth element, erbium ion as dopant into the host glass has affected physically, thermally and optically of the glasses. The amorphous nature of the glasses was confirmed by XRD (x-ray diffraction). Thermal exo-endothermic event profiles clarify its glass transformation temperature Tg, crystallization temperature Tx, and melting temperature Tm are exist. Both UV-Vis-NIR optical absorption and Raman spectroscopy have revealed optical energy gap changes due to the structural deformation by the erbium ions. Related obtained glass parameters such as polarizability, refractive indices and metallization criterion were also explained further in this study.
A B S T R A C T BaO-TeO 2 glasses containing 10 to 20-mol% BaO were studied by X-ray diffraction, density, thermal analysis, UV–visible and Raman spectroscopy. The effects of Eu 3 + , Dy 3 + , Er 3 + and Nd 3 + on the density, thermal, optical absorption and luminescent properties of barium tellurite glasses were studied. The short-range structure of barium tellurite glasses consists of TeO 4 trigonal bipyramidal and TeO 3 trigonal pyramidal units. TeeO coordination (N TeeO) was determined by Raman studies; it was found that that N TeeO decreases with increase in BaO and rare earth oxide concentration. The glass transition temperature is a function of both the average single bond enthalpy and non-bridging oxygen concentration in the glass network. Glasses containing Dy 3 + and Eu 3 + show strong visible light photoluminescence, and our results show that barium tellurite glasses are suitable hosts for rare earth ion luminescence due to low phonon energies.
Band gap and polarizability of boro-tellurite glass: Influence of erbium ions
Journal of Molecular Structure, 2014
Understanding the influence of rare earth ions in improving the structural and optical properties of inorganic glasses are the key issues. Er 3+-doped zinc boro-tellurite glasses with composition 30B 2 O 3-10ZnO-(60-x) TeO 2-xEr 2 O 3 are prepared (x= 0, 0.5, 1, 1.5 and 2 mol%) using melt quenching technique. The physical and optical characterizations are measured by density and UV-Vis-IR absorption spectroscopy. The color of the glass changed from light yellow to deep pink due to the introduction of Er 3+ ions. The maximum density is found to be ~4.73 gr.cm-3 for 1 mol% of Er 3+ doping. The variations in the polarizability (6.7-6.8 cm 3) and the molar volume (27.987-28.827 cm 3 mol-1) with dopant concentration are ascribed to the formation of non-bridging oxygen. This observation is consistent with the alteration of number of bonds per unit volume. The direct and indirect optical band gaps are increased while the phonon cutoff wavelength and Urbach energy decreased with the increase of erbium content. A high density and wide transparency range in VIS-IR area are achieved. Our results on high refractive index (~2.416) and polarizability suggest that these glasses are potential for photonics, solid state lasers and communications devices.
Journal of Non-Crystalline Solids, 2017
Er 3+ doped borosilicate glasses were prepared by standard method with the chemical composition (50 − x) B 2 O 3-(10 + x) SiO 2-10 Na 2 O-20 PbO-10 ZnO-0.3 Er 2 O 3 (where x = 0, 5, 10, 15, 20, 25, 30, 35, 40). The prepared glass samples were characterized by XRD, EDAX, FTIR, SEM and TEM. XRD reveals the amorphous nature of the glass samples. Various band positions are confirmed by the FTIR and borate network is present in the wavelength region 650-1700 cm −1. Elemental composition of the glass samples were observed by EDAX. Variation of physical and optical parameters with increasing concentration of SiO 2 affects the glass structure. Decrease in the value of Oxygen Packing Density (OPD) with increasing concentration of SiO 2 shows loosely packed structure of glass samples. Absorption and fluorescence spectra were recorded in Visible and NIR region at room temperature. Judd-Ofelt (JO) intensity parameters were calculated by using oscillator strength and the order of these parameters is Ω 2 N Ω 4 N Ω 6. Radiative properties were obtained by JO parameters and fluorescence spectra. A bright green emission is observed for the transition 2 H 11/2 , 4 S 3/2 → 4 I 15/2 and it is further confirmed by Commission Internationale de l' Eclairage (CIE) chromaticity diagram. 2 H 11/2 , 4 S 3/2 → 4 I 15/2 is suitable for green lasers. This gives the suitability of the present glass sample for fibre optics amplifier and photonic application.
Structural and luminescence behavior of Er3+ ions doped Barium tellurofluoroborate glasses
Er3+ doped Barium tellurofluoroborate glasses (BTFBxE) with the chemical composition (30 x)TeO2 + 30B2O3 + 20BaO + 20BaF + xEr2O3 (where x = 0.01, 0.05, 0.1, 0.5, 1.0 and 2.0 in wt%) were prepared following the melt quenching technique. The different vibrational modes of borates and tellurites in the prepared glasses were explored through FTIR and Raman spectra. The optical absorption spectra have been used to determine the ionic/covalent nature of the metal–ligand bond in the prepared glasses with the help of Nephelauxetic ratio (b) and bonding parameter (d) studies. The optical band gap of direct and indirect allowed transitions were determined from Tauc’s plot and the variations of band gap energy with structural arrangements were discussed. The Urbach energy values were determined and the relatively lower values of the Urbach’s energy reveal the minimal degree of disorderness in the prepared glasses. The oscillator strengths (fexp and fcal) and Judd–Ofelt (JO) intensity parameters (X2, X4 and X6) were calculated with the application of JO theory and the trends of the JO intensity parameters are found to be X2 > X6 > X4 for all the prepared glasses with a minimum variation in X2 intensity parameter values. A bright green emission was observed from the 2H11/2 + 4S3/2?4I15/2 transition and the radiative properties such as transition probability (A), stimulated emission cross-section (rEP ), branching ratio (br) and radiative lifetime (s) were calculated using the JO parameters. The suitability of the prepared glasses for the fabrication of photonic devices were also discussed and reported in the present work.
DEDUCTION OF THE LUMINESCENCE PARAMETERS OF TELLURIUM OXIDE BASED GLASSES DOPED WITH Er 3+ IONS
Quaternary glasses within system 75TeO 2 -10Nb 2 O 5 -10ZnO-5PbO doped with different concentration of Er 2 O 3 ions were prepared. The Judd-Ofelt parameters 2 , 4 , 6 , the oscillator strength type transition probabilities, spectroscopic quality factors, branching ratio and radiative lifetimes of several excited states of Er 3+ have been evaluated. The gain crosssection of laser transition level from 4 I 13/2 → 4 I 15/2 was obtained. 75TeO 2 -10Nb 2 O 5 -5PbO-10ZnO-8750 ppm Er 2 O 3 has the highest effective emission cross section bandwidth (66.3nm) and large stimulated emission cross-section equal 27.9610 -21 cm 2 . Spectroscopic properties indicate that this glass doped with Er 3+ is a promising candidate for optical applications.
Journal of Non-Crystalline Solids, 2017
The GeO 2-PbO-Bi 2 O 3-SrF 2 (GePbBiSr) glass systems doped with Eu 3+ , Tb 3+ , Tm 3+ and triply-doped with Eu 3+ / Tb 3+ /Tm 3+ ions were successfully synthesized. Their structural and luminescent properties have been investigated with various techniques. Obtained results indicate that these glass systems are suitable materials for the RE 3+ ions hosts. RE 3+ ions can be excited by single UV light wavelength (355/378/395 nm) and simultaneously emit red, green and blue light originating from Eu 3+ , Tb 3+ and Tm 3+ transitions. Emission color changes from bluish-purple for 355 nm excitation to white when irradiated with 378 nm and 395 nm. The GePbBiSr glass triply-doped by Eu 3+ /Tb 3+ /Tm 3+ ions could be a potential candidate for white LED applications.
Optical Materials, 2013
Structural and optical properties of Eu 3+ and Dy 3+ ions in PbO-Ga 2 O 3-XO 2 (X = Te, Ge, Si) glasses have been examined using X-ray diffraction, FT-IR and luminescence spectroscopy. Several crystalline phases such as TeO 2 , PbTe 3 O 7 , PbO and PbO 2 were identified in lead tellurite system using X-ray diffraction analysis, in contrast to PbO-Ga 2 O 3-XO 2 (X = Ge, Si) glass samples. Characteristic emission bands due to the 5 D 0 ? 7 F J (J = 0-4) transitions of Eu 3+ and the 4 F 9/2 ? 6 H J/2 (J = 15, 13, 11) transitions of Dy 3+ were registered. Two spectroscopic parameters, such as luminescence intensity ratios associated to 5 D 0 ? 7 F 2 and 5 D 0 ? 7 F 1 transitions of Eu 3+ as well as 4 F 9/2 ? 6 H 13/2 and 4 F 9/2 ? 6 H 15/2 transitions of Dy 3+ , and luminescence lifetimes for excited states of rare earth ions were determined. The luminescence intensity ratios for Eu 3+ and Dy 3+ ions decrease, whereas 5 D 0 (Eu 3+) and 4 F 9/2 (Dy 3+) luminescence lifetime increases, when covalence between Ln 3+ and O 2À ions is reduced and the phonon energy of the host glass is increased in PbO-TeO 2 ? PbO-GeO 2 ? PbO-SiO 2 direction. It was confirmed by FT-IR measurements.
Physical properties of some rare earth tellurite glasses
Mossbauer and IR spectra as well as the electrical conductivity have been measured to give an idea about the structure and the electrical properties of some rare earth tellurite glasses containing Fez03. The glasses denoted [1-(2x + 0.05)] Te02" xFe203 • (x + 0.05) Ln203, where x = 0.0 and 0.05 and Ln = lanthanum, neodymium, samarium, europium or gadolinium, were prepared by fusing a mixture of their respective reagent grade oxides in a platinum crucible at 800°C for one hour. The Mossbauer parameters such as isomer shift, quadruple splitting and line width were found to be a function of the polarizing power (charge/radius) of the rare earth cations. The Mossbauer parameters were not affected by the heat treatment of the glass samples. Both of the Te-O-Ln and Te-O-Fe stretching vibrations were obtained from the IR results which indicate that the rare earth oxides and iron oxide are partially covalent. The electrical resistivity was measured as a function of temperature from 293 to 520 K. Both the electrical resistivity and the activation energy were found to be a function of the atomic number (Z) of the rare earth cations. The results were interpreted on the basis of the electronic structure of the glass.
Optical Properties of Rare‐Earth Ions in Lead Germanate Glasses
Journal of the …, 1998
2 ؒ1Ln 2 O 3 , with x = 30 mol% (Ln = Nd, Eu, Er), 40 mol% (Ln = Pr, Nd, Sm, Eu, Dy, Ho, Er, Tm), and 50 mol% (Ln = Eu, Er), have been prepared by quenching the oxidic melts. From the optical absorption and emission spectra in the ultravioletvisible-near-infrared (UV-VIS-NIR) region, the intensity parameters, spontaneous emission probabilities, branching ratios, radiative lifetimes, and, for selected NIR transitions, peak stimulated emission cross sections have been obtained. The trends observed in the intensity parameters have been discussed, as a function of the number of f electrons as well as a function of the lead content. As the amount of lead increases, the covalency of the Ln−O bond increases, the symmetry of the rare-earth site increases, and the dopant site distribution narrows. The peak stimulated emission cross sections rank among the highest found for oxide glasses. J ournal 2045 Fig. 4. NIR emission spectra of lead germanate glasses doped with (a) Nd 3+ , (b) Ho 3+ , and (c) Er 3+ ions for laser excitation at 632.8 nm (the spikes at 1.27 m are second-order peaks of the excitation wavelength).
Structural and optical properties of TeO2-Li2O-ZnO-Nb2O5-Er2O3 glass system
Journal of Non-Crystalline Solids, 2018
Quinary tellurite glass system in the percentages of 75TeO 2-5Li 2 O-10ZnO-(10-x) Nb 2 O 5-xEr 2 O 3 where (x = 0.0, 0.5, 1.0, 1.5, 2.0, and 2.8 mol%) have been prepared and characterized. Both Fourier-transform-infrared (FTIR) and Raman spectroscopies were performed to study the structural changes correlated with the glass network. The thermal characteristics of the system were specified which showed a higher thermal stability (> 100°C) due to the formation of more bridging oxygen's (BO's) revealed by (FTIR) and Raman spectroscopies. The optical absorption spectra within near UV-visible regions were performed, and exhibited nine absorption bands centered around 1536, 977, 798, 653, 545, 524, 490, 450, and 443 nm corresponding to the 4 I 15/2 ground state to the various excited states 4 I 13/2 , 4 I 11/2 , 4 I 9/2 , 4 F 9/2 , 4 S 3/2 , 2 H 11/2 , 4 F 7/2 , 4 F 5/2, and 4 F 3/2 respectively. The same measurement also showed increasing values of the optical band gap (E g) form 2.70 to 2.90 (eV) and decreasing the refractive index (n) from 2.48 to 2.42. Both the extinction coefficient data and the complex dielectric functions of the glasses were estimated. The different optical parameters were distinctly affected by increasing the Er 2 O 3 (mol %) and the structural changes. The radiative properties of the glass were calculated using J-O parameters. The Branching ratio (β) of 4 I 13/2 → 4 I 15/2 transition peaked at 1520.48 nm for Er 3+ ions has the highest value (1.000) also, the radiative lifetime (τ) of the same transition changed from 1.4510 to 1.8483. The gain cross-section of the laser transition level from 4 G 11/2 → 4 I 15/2 changed from 1.44 × 10 −20 to 1.92 × 10 −20 cm −1 in the existing glass system. The acquired results exhibited that the existent glass can be a good candidate in the fiber drawing and laser, non-linear optical applications.
Sm 3þ ions doped Alkaline-Earth Boro Tellurite (AEBT) glasses were prepared by using conventional melt quenching technique and characterized using the spectroscopic techniques such as FT-IR, optical absorption , emission and decay spectral measurements to understand their utility in optoelectronic devices. From absorption spectra, the bonding parameters, nephelauxetic ratios were determined to know the nature of bonding between Sm 3þ ions and its surrounding ligands. From the measured oscillator strengths, the Judd-Ofelt (J-O) intensity parameters were evaluated and in turn used to estimate various radiative parameters for the fluorescent levels of Sm 3þ ions in AEBT glasses. The PL spectra of Sm 3þ ions exhibit three emission bands corresponding to the transitions 4 G 5/2 / 6 H 5/2 , 6 H 7/2 and 6 H 9/2 in the visible region for which the emission cross-sections and branching ratios were evaluated. The decay spectral profiles measured for 4 G 5/2 / 6 H 7/2 transition showed single exponential for lower concentration and non-exponential for higher concentration of doped rare earth ion in the as prepared glasses. Conversion of decay spectral profiles from single to non-exponential have been analyzed using InokutieHirayama (I eH) model to understand the energy transfer mechanism involved in the decay process. CIE Chromaticity coordinates were measured using emission spectral data to identify the exact region of emission from the as-prepared glasses. From the evaluated radiative parameters, emission cross-sections and quantum efficiencies, it was observed that AEBT glass with 1 mol% of Sm 3þ ions is more suitable for designing optoelectronic devices.
Spectroscopic properties of lead fluoroborate glasses codoped with Er^3+ and Yb^3+
Journal of The Optical Society of America, 2002
A new glass of heavy metal oxide (25.0Bi 2 O 3 -57.0PbO-18.0Ga 2 O 3 (mol%)) doped with Yb 3þ is presented and compared with lead fluoroborate glass (43.5H 3 BO 3 -22.5PbCO 3 -34.0PbF 2 (mol%)), also doped with ytterbium. The interest in Yb 3þ for laser action and short pulse generation under diode pumping has been reported in the literature. Spectroscopic properties were studied for both glasses doped with 0.5 mol% of Yb 2 O 3 . The absorption cross-section of the heavy metal oxide glass is ð2:20 AE 0:15Þ Â 10 À20 cm 2 at the absorption peak wavelength of 968 nm and its emission cross-section is ð0:75 AE 0:05Þ Â 10 À20 cm 2 at the extraction wavelength of 1012 nm. A fluorescence effective linewidth of 86 nm and a fluorescence lifetime of 0.40 ms were measured. In the case of the lead fluoroborate glass used for comparison, these values change to ð2:56 AE 0:18Þ Â 10 À20 cm 2 (absorption cross-section), ð1:07 AE 0:08Þ Â 10 À20 cm 2 (emission cross-section at 1022 nm), 60 nm (fluorescence effective linewidth) and 0.81 ms (fluorescence lifetime). Calculations of the minimum pump intensity are also presented. Both have spectroscopic properties for laser applications that are similar to those of other known glasses (phosphate and tellurite laser glasses) used as active laser media. The large emission bandwidth measured for the heavy metal oxide is of interest for tunable lasers. Ó
Journal of Luminescence, 2020
Praseodymium (Pr2O3) doped PbO-Ro2O3-WO3-B2O3 glasses were prepared by melt quenching method and their optical absorption and emission spectra were characterized, for three different heavy metal oxides (Ro2O3 = Sb2O3, Al2O3, and Bi2O3). The characteristics of the glass matrix are confirmed by X-ray diffraction spectra. Many structural properties can be identified by Fourier Transform infrared spectra of the glasses, such as PbO, B2O3, and WO3. From the optical absorption spectra, the absorption edges, and the values of direct and indirect band gap transitions and Urbach energies were calculated. The oscillator strengths of the absorption bands were determined by the Judd-Ofelt model, and the Judd-Ofelt intensity parameters Ω_2, Ω_4, and Ω_6 were calculated for each of the studied glasses. Moreover, the nephelauxetic ratio β, bonding parameter δ, and optical basicity Λ^th were also calculated to characterize the bonding nature of the Pr3+ rare-earth ions. From the emission spectra, spontaneous radiative transition probability A_τ, total radiative transition probability A_T, luminance branching ratio β_r, and radiative life time τ_rad were calculated. From the spectra, the CIE color coordinates were also calculated for all the studied glasses. This research confirms that the studied materials are suitable for red laser applications.