Physical and luminescence properties of samarium doped oxide and oxyfluoride phosphate glasses (original) (raw)
Related papers
Journal of Electronic Materials, 2020
Luminescent phosphate glasses having the composition 40P 2 O 5-30ZnO-20BaF 2-3.8K 2 TeO 3-1.2Al 2 O 3-5Nb 2 O 5 in mol.% doped with 3 9 10 3 ppm and 4 9 10 3 ppm Sm 2 O 3 were successfully prepared by a melt-quenching technique. The investigated glasses were characterized by x-ray diffraction, UVvisible-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: X 2 > X 4 > X 6. 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 Sm 3+ content, which is explained on the basis of structural changes. The calculated stimulated emission cross-section r SE ; at 1.62 lm of glasses studied was high, and increased from 3.81 9 10 À21 cm 2 to 4.38 9 10 À21 cm 2 with increasing Sm 3+ ion concentration. The structure of the glasses was investigated by computing Internuclear r i ð Þ, Polaron radius r p À Á and field strength F ð Þ and measurement of Raman spectra.
Optik, 2018
Luminescence mechanism of RE doped glasses is significant in optical devices, the glasses of compositions (80-x) P2O5-20CaSO4-(x) Sm2O3 with 0.3 ≤ x ≤ 1.5 mol% have been prepared by melt-quench method. The result of XRD patterns affirmed the amorphous nature of the samples. The structure was investigated successfully using FTIR, NMR and Raman in order to examine the molecular vibrational modes and to verify the de-polymerization process. Absorption and photoluminescence spectra of Sm2O3 doped calcium ultra-phosphate glasses have been reported. Three emission band of Sm 3+ centered at 4 G5/2→ 6 H9/2 (642 nm), 4 G5/2→ 6 H7/2 (597 nm) and 4 G5/2→ 6 H5/2 (559 nm) have been observed at λexc= 402 nm. The spectroscopic research reveals the de-polymerization pattern in P2O5 glass structure by conversion of Q3→Q2→Q1 and to Qo units. Physical and optical properties were investigated, doped ions were successfully position at interstice spaces in CSP, the physical properties such as, density, Polarizability, Molar refractivity, and refractive index etc, have been estimated. The absorption spectra in the wavelength range 900-1700 nm were determined, the spectra consist of seven absorption peaks corresponds to transitions from 6 H5/2 ground state to excited state. From the absorption edge spectra, the band gap (direct and indirect) and the Urbach energy (ΔE) values were evaluated. The conventional JO (Judd-Ofelt) intensity parameters (Ω2, Ω4 and Ω6) and root mean square (δrms) deviation have been evaluated and discussed with respect to Sm 3+ concentration. Obtained result goes along with the Sm 3+ doped magnesium zinc sulfo-phosphate glasses for advancement of many functional glasses.
Spectroscopic and radiative properties of Sm3+- doped phosphate glasses
Sm 3 þ -doped K-Mg-Al phosphate glasses were prepared and characterized through various spectroscopic techniques such as optical absorption, excitation, photoluminescence spectra and decay rate analysis at room temperature to derive spectroscopic and radiative properties of Sm 3 þ ions in these glasses. Energy parameters for the 4f 5 electronic configuration of Sm 3 þ ion in K-Mg-Al phosphate glass have been determined using free-ion Hamiltonian model. Judd-Ofelt (JO) analysis has been applied to evaluate the JO intensity parameters, O l (l¼ 2, 4 and 6), and in turn radiative properties such as radiative transition probability, branching ratio, radiative lifetime and peak stimulated emission crosssection for the fluorescent 4 G 5/2 level of Sm 3 þ ion have been determined. The fluorescence decay rates exhibit single exponential at lower concentrations (r 0.1 mol%) and turn into non-exponential at higher concentrations (Z 0.5 mol%). The experimental lifetime for the 4 G 5/2 level as a function of Sm 3 þ ions concentration decreases from 2.77 to 0.74 ms when the concentration is increased from 0.05 to 2.0 mol% of Sm 2 O 3 due to energy transfer process. The non-exponential decay rates are well-fitted to Inokuti-Hirayama model for S ¼ 6 indicating that the nature of the energy transfer process is of dipoledipole type. The systematic analysis on decay rates indicates that the energy transfer mechanism depends on Sm 3 þ ion concentration as well as glass composition.
White light emission of dysprosium doped lanthanum calcium phosphate oxide and oxyfluoride glasses
Optical Materials, 2017
Lanthanum calcium phosphate oxide and oxyfluoride glasses doped with dysprosium oxide were prepared by melt-quenching technique with chemical composition 20La 2 O 3 :10CaO:69P 2 O 5 :1Dy 2 O 3 and 20La 2 O 3 :10CaF 2 :69P 2 O 5 :1Dy 2 O 3. The physical, optical and luminescence properties of the glass samples were studied to evaluate their potential to using as luminescence materials for solid-state lighting applications. The density, molar volume and refractive index of the glass samples were carried out. The optical and luminescence properties were studied by investigating absorption, excitation, and emission spectra of the glass samples. The absorption spectra were investigated in the UVeVis eNIR region from 300 to 2000 nm. The excitation spectra observed under 574 nm emission wavelength showed the highest peak centered at 349 nm (6 H 15/2 / 6 P 7/2). The emission spectra, excited with 349 nm excitation wavelength showed two major peaks corresponding to 482 nm blue emission (4 F 9/ 2 / 6 H 15/2) and 574 nm yellow emission (4 F 9/2 / 6 H 13/2). The experimental lifetime were found to be 0.539 and 0.540 for oxide and oxyfluoride glass sample, respectively. The x,y color coordinates under 349 nm excitation wavelength were (0.38, 0.43) for both glass samples, that be plotted in white region of CIE 1931 chromaticity diagram. The CCT values obtained from the glass samples are 4204 K for oxide glass and 4228 K for oxyfluoride glass corresponding to the commercial cool white light (3100 e4500 K). Judd-Ofelt theory had also been employed to obtain the J-O parameters (U 2 , U 4 and U 6), oscillator strength, radiative transition possibility, stimulated emission cross section and branching ratio. The U 2 > U 4 > U 6 trend of J-O parameters of both glass samples may indicate the good quality of a glass host for using as optical device application. Temperature dependence of emission spectra was studied from 300 K to 10 K and found that the intensity of the emission peak was found to be increased with decreasing of the temperature. The results of the investigations in this work confirmed that the present Dy-doped lanthanum calcium phosphate oxide and oxyfluoride glasses perform high potential for using as efficient luminescence materials for solid-state lighting applications, especially for white LEDs. Furthermore, the oxyfluoride glass sample provides more luminescence potential than the oxide glass sample.
Journal of Materials Science: Materials in Electronics, 2023
A spectroscopy study was performed to investigate the absorption and emission behavior of zinc-lead phosphate-doped Sm 3? glasses sample. The parameters, density, q, molar volume, V m , samarium ion concentration N, and mean samarium ion separation, R were calculated. The absorption peaks were assigned and discussed. The band gap and Urbach's energies analysis were illustrated. The emission spectra and the emission lifetime decay were studied. The CIE diagram coordinate (0.393, 0.601) of the sample's emission was very close to the TV standard value. The oscillator strength f cal and f exp were calculated using Judd-Ofelt theory, and the model parameter trend was found to be X 4 [ X 2 [ X 6 which indicates high glasses rigidity. The Absorption and emission cross-sections were studied and illustrated. The obtained optical parameters, absorption, and emission behaviors introduce the samples under investigation as a candidate for orange and reddish-orange photonic applications.
Journal of Molecular Structure, 2015
Spectroscopic properties of Dy 3+ doped different FP glasses are studied. Higher covalency is observed in the sodium fluoro-phosphate (FP) glasses. Sodium FP glass has highest luminescence intensity at 577 nm than other FP glasses. FP glasses can be useful for white light emission. g r a p h i c a l a b s t r a c t a b s t r a c t Dy 3+ doped different fluoro-phosphate glasses are prepared and they are characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Raman, optical absorption, and photoluminescence (PL) techniques. The structural characterization is accomplished by XRD, FTIR and Raman spectroscopy. The morphological analysis was performed by SEM. The absorption spectra have been analyzed using Judd-Ofelt theory and the intensity parameters have been evaluated. These parameters are used to calculate radiative properties such as emission probabilities (A R ), radiative lifetimes (s R ) and integrated absorption cross-sections (R) for different Dy 3+ transitions. The PL spectra exhibit bands in the blue, yellow and red regions. Furthermore, the dependence of luminescence properties such as stimulated emission cross-sections (r p ) and branching ratios (b) on different metal cations in these glasses is studied. From decay curve analysis, the lifetimes of the excited state 4 F 9/2 have been measured. The calorimetric property is also studied based on Commission International del'Eclairage (CIE) standards for Dy 3+ doped different fluoro-phosphate glasses and discussed.
Journal of Luminescence, 2016
The multicomponent fluoro-phosphate glasses of the type, 49.5P 2 O 5 -10AlF 3 -10BaF 2 -10SrF 2 -10PbO-10M (M= Li 2 O, Na 2 O, K 2 O, ZnO and Bi 2 O 3 ) doped with 0.5 mol % neodymium were prepared by melt quenching technique. Their structures were characterized by the X-ray diffraction with SEM analysis, Fourier transform infrared (FTIR), Raman spectroscopy and 31 P and 27 Al magic angle spinning (MAS) nuclear magnetic resonance (NMR) techniques. XPS spectra were studied to know the bridging and non-bridging oxygen groups. X-ray absorption near edge spectroscopy (XANES) was used to study the electronic structure of neodymium in the host glass matrices. The Judd-Ofelt parameters (J-O) (Ω 2 , Ω 4 and Ω 6 ) were evaluated from the intensities of the absorption bands through optical absorption spectra. Further, J-O parameters have been used to calculate various radiative properties like probabilities of radiative transitions, radiative lifetimes and branching ratios for different fluoro-phosphate glasses. The luminescence kinetics from the excited neodymium levels have been studied upon selective excitation through photoluminescence measurements. Neodymium ion emits two near infrared laser emissions: 4 F 3/2 → 4 I 11/2 at 1.06 μm and another one 4 F 3/2 → 4 I 13/2 at 1.32 μm. The major intensity is observed for 1.06 μm for the prepared fluoro-phosphate glasses. The lifetimes of these levels have been experimentally determined through decay profile studies. The above results suggest that the prepared lithium fluoro-phosphate glass system could be a suitable candidate for using it as 1.06 μm laser source in the near infrared region of spectrum.
Journal of Luminescence, 2015
The fluorescence properties of different concentrations of Sm 3 þ doped zinc-aluminum-sodium-phosphate (ZANP) glasses were studied by the XRD, SEM, FTIR, TG-DTA, optical absorption, photoluminescence and decay cure analysis. X-ray diffraction profiles and SEM images confirmed the amorphous nature of the glass samples. Structural information of these glass matrices was provided by FTIR spectrum. Judd-Ofelt (J-O) theory was applied to the experimental oscillator strengths to evaluate three phenomenological J-O intensity parameters, Ω λ (λ¼ 2, 4 and 6). Using J-O intensity parameters and emission spectra, various radiative parameters such as radiative transition probabilities (A R ), radiative lifetimes (τ R ), calculated and measured branching ratios (β R and β m ), effective bandwidths (Δλ eff ) and stimulated emission cross-sections (σ P ) were calculated for observed emission transitions. The intensity of emission transitions with the variation of Sm 3 þ ion concentration was studied. The nature of decay curves of 4 G 5/2 level for different Sm 3 þ ion concentrations in ZANP glass was analyzed and obtained measured lifetimes (τ exp ). Quantum efficiency of 4 G 5/2 level was calculated based on experimental and measured radiative lifetimes (τ exp and τ R ).
Comparative study of luminescence and optical properties of Sm3+ doped glasses with different hosts
2018
The spectoscopic properties of Lithium-gadolinium-borate and Zinc-barium-borate glasses doped with samarium ions had been published in previous studies and metaphorical results were investigated. The samarium-doped lithium-gadolinium-borate glasses [60Li 2 O:10Gd 2 O 3 :(30-x) B 2 O 3 :xSm 2 O 3 ] where x = 0.05, 0.10, 0.50, 1.00 and 1.50 mol% and zinc-barium-borate glasses [(60-x)B 2 O 3 :30BaO:10ZnO: xSm 2 O 3 ] where x= 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol% have been prepared by the same method. The absorbtion spectra are similar in transitions from the ground state 6 H5/2 to the excited states with minor difference. Both glass system gave the emission spectra with peaks at 562, 600, 646, 707 nm arise from the transition 6 H 5/2 , 6 H 7/2 , 6 H 9/2 , and 6 H 11/2 respectively, under 404 nm excitetation ligth. The concentration quenching effect (CQE) was found at 1.0 mol% of the dopant for LGBO: Sm 3+ , due to not observed for ZBaB: Sm 3+. Both glass systems doped with Sm 3+ .