Optical and luminescence characteristics of Eu3+-doped B2O3:SiO2:Y2O3:CaO glasses for visible red laser and scintillation material applications

Abstract

Europium (Eu3+) doped glasses of chemical compositions (55−x)B2O3:10SiO2:25Y2O3:10CaO:xEu2O3, where x denotes mol% and ranges 0 ≤ x ≤ 2.5, were synthesized by adopting conventional melt quenching technique. Physical properties like density, molar volume, polaron radius, inter-ionic distance and field strength of the glass samples were investigated to assess the impact of Eu2O3. Optical and luminescence properties of the glasses were characterized with optical absorption, photoluminescence, X-ray induced emission spectra, temperature dependence emission spectra and decay times. Judd-Ofelt (JO) intensity parameters (Ωλ) of the glasses were evaluated based on the absorption spectrum of 0.5 mol%. JO parameters, calculated from absorption spectra with thermal corrections on oscillator strength, were used to evaluate radiative properties such as radiative transition probability (AR), branching ratio (βR), stimulated cross section emission (σ) and radiative lifetime (τR) for 5D0 → 7FJ (J = 0,1,2,3 and 4) transitions. The decay rate of 5D0 fluorescent level for all the glass samples was single exponential. Lifetimes of the 5D0 level were decreased with increasing concentrations of Eu3+ions from 0.05 mol% to 2.5 mol% which might be due to energy transfer through cross-relaxation in the glasses. The chromaticity coordinates (x, y) were similar for all BSYCaEu glasses and were located at the red region of CIE 1931 color chromaticity diagram. Hence, these results confirm that the Eu3+ doped BSYCaEu glasses could be useful for visible red lasers and glass scintillation applications.