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A new glass with a composition of 40P2O5-30ZnO-20LiCl-10BaF2 (in mol%), doped with 3.5Nd2O3-3.5Yb2O3, was fabricated by the quenching melt technique. The luminescence (PL) and gamma spectroscopy of the glass were investigated systematically. The spectroscopic parameters of the prepared glass, such as the optical energy gap, Judd–Ofelt parameters Ωk (where k = 2, 4 and 6), lifetimes and branching ratio of the Nd3+/Yb3+ level, were evaluated. Moreover, the shielding parameters, such as the linear and mass attenuation coefficients, mean free path and half-value layer, were evaluated. The prepared glass had a spectroscopic quality factor (Ω4/Ω6) of 0.84, which is about three-times larger than that of the most standard laser host, Nd3+:YAG. The energy of the 2P1/2 (Nd3+) level (~23,250 cm−1) was twice the energy of the Yb3+ transition (~10,290 cm−1). The value of the emission cross section ( σ e m (λ) ) of Nd3+:4F3/2→4I9/2 and Yb3+:2F5/2→2F7/2 were 2.23 × 10−24 cm2 and 2.88 × 10−24 cm2, respectively. The fabricated glass had a high emission cross section and low mean free path parameters, which makes the fabricated glass a potential candidate for multifunctional applications, such as laser emissions for medical purposes. [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]

A series of fluorotellurite glasses based on 70TeO2-5MxOy-10P²O5-10ZnO-5PbF2 in mol%, where MxOy = (WO3, Nb2O5) doped with 2400 ppm of Er2O3 have been prepared by the conventional melt quenching method. The influence of modifiers on thermal and optical properties of glasses has been analyzed. Thermal characteristics of glasses like the glass transition temperature Tg, the temperature for the crystallization onset Tx, the maximum crystallization temperature Tc, and the thermal stability parameter were determined by the DSC method. The ellipsometric data have provided Sellmeier-type dispersion relations of the refractive index of the investigated glasses. The optical parameters are used to calculate the molar refractivity, molar polarizability, oxide ion polarizability, molar cation polarizability, and a number of polarizable atoms per unit volume for every glass composition in order to interpret the refractive index of these glasses. [ABSTRACT FROM AUTHOR]

We have investigated the thermal and spectroscopic properties of Pr 3+ -doped new tellurite matrix with the molar composition 60%TeO 2 –27%WO 3 –10%PbO–3%Lu 2 O 3 (TWPLu). The differential thermal analysis has shown that addition of Lu 2 O 3 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 Pr 3+ -doped TWPLu glasses have been analyzed in terms of the standard Judd–Ofelt theory along with the luminescence decay of the 3 P 0 and 1 D 2 levels of the Pr 3+ ion. A significant influence of the Pr 3+ 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. [ABSTRACT FROM AUTHOR]

The paper presents new glass-ceramics as a material for up-conversion luminescence. Formation of the LaF3 nanocrystals have been obtained as a low phonon host for rare earth active ions in oxide glassy matrix. The thermal conditions of LaF3 nanocrystallization in the glass from the SiO2-Al2O3-Na2O-LaF3 system have been presented. Transmittance and luminescence properties as a function of heat treatment have been investigated. The effect of incoming of Er3+ in LaF3 crystals has been shown on the luminescence properties. AFM results have confirmed the growth of nano-scale crystals. [ABSTRACT FROM AUTHOR]

• High optical quality borosilicate glasses doped with Dy 2 O 3 were fabricated. • Aluminum borosilicate glasses doping with Dy3+ can used as luminescent device applications for white light generation. • The present glasses have high magnitudes of emission cross-section and branching ratio, which is important in laser applications. • Higher asymmetrical degree of present matrix around Dy3+ ions, and strong covalent bonding nature with surrounding atoms. • The luminescence performance of fabricated glasses showed a strong transition. We manufactured a new series of borosilicate glass doped with Dy3+ ions using a glass-quenching technique. To achieve the unique luminescence properties of our prepared glass, rare earth (Dy 2 O 3) was incorporated into the glass matrix. The photoluminescence spectrum revealed five intense emission bands allocated at wavelengths 483 nm, 575 nm, 665 nm, 712 nm, and 752 nm, attributed to the transition from 4F 9/2 → 6H 15/2 , 4F 9/2 → 6H 13/2 , 4F 9/2 → 6H 11/2 , 4F 9/2 → 6F 3/2 , and 4F 9/2 → 6H 9/2 respectively. From the emission results of prepared glass at excitation wavelength 350 nm, we used our glass as a new solid laser source for the production of white light. From radiative properties measurements, the luminescence performance of fabricated samples showed a strong transition, with limited transition life and high values of branching ratio. Additional physical parameters were evaluated, such as density, optical packing density, and molar volume. By X-ray diffraction, we observed that all the prepared samples were of the amorphous phase. Fourier Transform Infrared Spectroscopy demonstrated the effect of incorporating Dy 2 O 3 on the structure of our prepared glass. From the spectrum of absorption transitions, optical band gap E g , refractive index (n), and Urbach energy (ΔE) were obtained. To research glass bonding nature, Judd-Ofelt strength parameters (Ω λ and λ = 2, 4, 6) were obtained; these parameters were used to achieve the spectroscopic efficiency factor, branching ratios (βr), and lifetime (τ). Moreover, the cross-sections of emission and absorption of our prepared glass was estimated. Finally, our cumulative study findings indicate that these manufactured samples may be used in luminescent display devices as a white light laser diode (W-LED). [ABSTRACT FROM AUTHOR]