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Abstract Present study reports the effects of varying concentrations of Pr3+ ions on the optical properties of 10ZnO-5Na 2 CO 3 -10Bi 2 O 3 -75-xB 2 O 3 -xPr 6 O 11 (x = 0.1–1 mol%) glasses prepared through melt-quench technique with an aim to achieve suitable optical gain medium for optoelectronic applications. Minimal changes in the measured density, X-Ray diffractogram and Fourier Transform Infrared spectra of the prepared samples confirmed the stability of the glass structure even after 1 mol% doping of the Pr3+. Bonding nature of Pr3+ ion with surrounding ligands and Judd-Oflet (J-O) intensity parameters of the glasses were determined using optical absorption spectra. The photoemission spectra exhibited reddish orange emission around 605 nm at 445 nm excitation. The calculated color chromaticity with x = 0.5847, y = 0.3701 coordinates for 0.1 mol% of the Pr3+ in the glasses suggests suitable optical gain medium for reddish orange LED applications. Metastable lifetimes of the Pr3+ ion were found-out by exponential fitting to the decay profiles. Lasing parameters of the glasses such as branching ratio, radiative transition probability and stimulated emission cross-section of 1D 2 →3H 4 transition were calculated using JO parameters indicating 0.1 mol% Pr3+-doped glasses suitable for 605 nm solid-state laser applications. The mechanism of energy transfer is determined by applying the Inokuti-Hirayama model and was found to involve a dipole-dipole type of interactions. Thermoluminescence (TL) glow curves of the gamma-ray treated 0.1 mol% Pr3+-doped zinc sodium bismuth borate glasses were de-convoluted using Computerized Glow Curve Deconvolution method to evaluate the energy storage properties of the glasses. The intensity variation of the TL component peak (CP2) at 500 K showed linear behavior up to 3 kG y suggesting application in high dose measurements. Graphical abstract Image 1 Highlights • Praseodymium doped zinc sodium bismuth borate glasses were prepared by melt quench technique. • The negative value of the bonding parameter revealed the ionic bonding between the Pr3+ ions with surrounding oxygen. • Hypersensitive transitions 3H 4 →3F 3 and 3H 4 →3P 2 of Pr3+ ions exhibited maximum values of oscillator strength values. • JO intensity parameters of 0.1 mol% Pr3+ doped glass showed very high rigidity and symmetry around Pr3+ ions. • CIE chromaticity diagram confirmed reddish orange color emission of these glasses under the 445 nm excitation. • Deconvoluted TL curve of fitted with 5 peaks and peak at 505 K showed linear dose response up-to 3 kGy gamma ray. [ABSTRACT FROM AUTHOR]

Zinc sodium bismuth borate (ZNBB) glasses doped with different concentrations of europium were prepared by conventional melt quenching method and characterized through the measurements of density, refractive index, X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectra, optical absorption, luminescence and radiative lifetimes. FTIR spectra showed seven characteristic peaks of bismuth and borate functional groups in the range of 400–1600 cm −1 . The optical band gap and bonding parameters have been calculated from absorption spectra. Photoluminescence spectra recorded in the visible region with 394 nm excitation are used to calculate the Judd-Ofelt (JO) intensity parameters (Ω 2 and Ω 4 ). The JO intensity parameters have been used to calculate the radiative parameters such as branching ratio (β), stimulated emission cross-section ( σ se ), transition probability (A) for the fluorescent level of 5 D 0 → 7 F 2 . Decay rates through single exponential are used to calculate the lifetime (τ m ) of the meta-stable state 5 D 0 of (Eu 3+ ion) these glasses. The radiative parameters measured for all these glasses show 0.7 mol% europium doped zinc sodium bismuth borate glass 5 D 0 → 7 F 2 transition has the potential for red laser applications. The quality of the colour emitted by the present glasses are estimated quantitatively by CIE chromaticity coordinates, which confirms the suitability of these glasses as a red emitting material for field emission technologies and LEDs. [ABSTRACT FROM AUTHOR]

Terbium (Tb 3+ ) doped oxyfluoro-titania-phosphate glasses of chemical composition (in mol%), (60 - x) P 2 O 5 – 15 BaF 2 – 20 CaF 2 – 5 TiO 2 – x Tb 4 O 7 , x = 0.05, 0.1 and 0.1 were fabricated by usual melt-quenching technique. Photoluminescence (PL) properties of the samples have been investigated by excitation, emission and decay profiles. Upon excitation at 377 nm, the PL spectra exhibit an intense band at 541 nm which corresponds to the 5 D 4 → 7 F 5 transition. The intensity ratio of green-to-blue (I G /I B ) was found to be 9.2 for 0.1 mol% of Tb 3+ -doped glass. High-energy absorption bands were not resolved in the absorption spectrum but disclosed in the photoluminescence excitation spectrum. Decay curves were unveiled non-exponential and mono-exponential behaviours for the 5 D 3 and 5 D 4 levels, respectively. Lifetime of the 5 D 3 and 5 D 4 levels was decreased up to 0.1 mol%, and thereafter it was increased with the increase of Tb 3+ ion concentration upon 377 nm excitation. The CIE chromaticity coordinates were supported that the green emission was predominant in Tb 3+ -doped oxyfluoro-titania-phosphate glasses. [ABSTRACT FROM AUTHOR]

Abstract Interaction of 10ZnO-5Na 2 O-10Bi 2 O 3 –74.3B 2 O 3 -0.7Eu 2 O 3 glasses exposed to high dose gamma rays were investigated using XRD, FTIR, absorption, photoluminescence followed by thermally and optically stimulated luminescence studies. XRD analysis confirmed the amorphous nature of glasses post-irradiation. Variation in FTIR spectra revealed, structural deformation of borate groups as a result of high dose gamma irradiation. Enhanced glass absorbance and red shift in absorption edge were observed with the increase in gamma dose. Further, radiation-induced absorption coefficient confirmed the trapped charges in the forbidden energy gap supported by Tauc's plot and Urbach energy. Photoluminescence (PL) study demonstrated quenching of luminescence intensity at higher gamma doses. Lifetime of metastable 5D 0 state of Eu3+ ions were estimated by the decay curves and color purity was calculated using 1931 CIE chromaticity coordinates (x,y). Thermally and optically stimulated luminescence studies reassured the existence of charges in trap centers due to irradiation. TL glow curve exhibited two broad emission peaks with the corresponding temperature being at 490 K and 625 K. Distinct TL peaks of the material and their kinetic parameters (E, S, τ and b) were determined via Computerized Glow Curve Deconvolution (CGCD) method. Linear behaviour obtained through the dose response of the glass (0.25–3 kGy) proved their suitability for dosimetric application in the food irradiation zones in addition to red LEDs (< 1 kGy). Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Abstract Dysprosium (Dy3+)-doped antimony-magnesium-strontium-oxyfluoroborate (B 2 O 3 MgF 2 SrO Sb 2 O 3 Dy 2 O 3 , BMFSrSbD), glasses were synthesized by traditional melt-quenching method. The synthesized samples have been analyzed by X-ray diffraction, optical absorption and fluorescence techniques for deriving various characteristic properties. Emission spectra of Dy3+: samples were exhibit three well resolved emission bands at around 482, 575 and 666 nm which originated from the 4F 9/2 →6H 15/2, 4F 9/2 →6H 13/2 and 4F 9/2 →6H 11/2 transitions upon excitation of wavelength at 452 nm. Decay curves of the 4F 9/2 level of Dy3+ ion were display mono-exponential at low Dy3+ concentration (0.1 mol%) and deviated to non-exponential behavior at high concentration of Dy3+ ions (≥ 0.5 mol%). Lifetime of the 4F 9/2 level was decreased with increase of Dy3+ ions concentration. Chromaticity coordinates (x,y) of Dy3+:BMFSrSbD samples were evaluated and represented in CIE 1931 chromaticity diagram, appear in the whitish-yellow region. The results suggest that these glasses could be utilized as a potential candidate for the development of display devices and lasers at a wavelength of 575 nm. [ABSTRACT FROM AUTHOR]

In this study, highly Eu3+ doped (up to 5 mol%) 10ZnO 40Bi 2 O 3 50B 2 O 3 glasses were prepared by melt quench process. The excitation and emission results of the prepared glasses were recorded in the visible region. The Judd Ofelt intensity and CIE chromaticity parameters of the glasses were calculated and discussed. The nonlinear optical properties of glasses were studied at a pumping wavelength of 532 nm under a nanosecond regime utilizing the sensitive Z scan technique. We investigated the linear attenuation coefficient (LAC) for the prepared glasses for energies ranging from 0.296 to 1.458 MeV. According to the Z eff results, 10ZnO 40Bi 2 O 3 45B 2 O 3 5Eu 2 O 3 exhibited good attenuation properties among the fabricated samples. [ABSTRACT FROM AUTHOR]

Trivalent samarium (Sm3+)-doped alkali-bismuth-germanate glasses of a composition (40-x) GeO 2 + 20 Bi 2 O 3 + 20 Na 2 O + 10 BaO + 10 Gd 2 O 3 + x Sm 2 O 3 (x = 0.05, 0.1, 0.5, 1.0, 1.5 and 2.5 mol%) (GeBiNaBaGdSm) were made from a typical melt-quenching procedure. An optical absorption, photoluminescence excitation, emission and decay curves of GeBiNaBaGdSm glasses were studied. For the 4G 5/2 → 6H 7/2 transition, an intense orange emission at 601 nm was observed when the Sm3+ ions pumped by 405 nm. A high value of 15.59 × 10−22 cm2 stimulated emission cross-section and 20.59 × 10−28 cm3 of optical gain bandwidth for the 1.5 mo% Sm 2 O 3 -doped GeBiNaBaGdSm15 glass were obtained. The experimental lifetime (τ exp) was increased up to GeBiNaBaGdSm05 glass, thereafter diminished with further increase of Sm3+ ion concentration. Decay profiles of Sm3+ ions were fitted using I-H model. Energy transfer rate (W ET) for GeBiNaBaGdSm10 glass is evaluated to be 554 s−1. The average red to orange (R/O) intensity ratio of these glasses is found to be 0.123. Furthermore, CIE chromaticity coordinates demonstrate that the emission was observed in the orange region and then shifted to red region with the increase of Sm3+ ion concentration. All the studies revealed that these glasses could be useful for tunable color display applications. • Samarium (Sm3+)-doped bismuth-germanate (GeBiNaGdBaSm) glasses have been synthesized by conventional melt-quenching technique. • Judd-Ofelt (JO) intensity parameters (Ω 2 , Ω 4 , Ω 6) have been evaluated from the absorption spectrum. • Radiative properties have been obtained by utilizing the JO parameters and refractive index. • CIE chromaticity coordinates have revealed a tunable emission from orange to red region. [ABSTRACT FROM AUTHOR]