Judd-Ofelt and laser parameters of Eu3+ ions doped in network restricted matrices

Abstract

Eu3+ ions were successfully doped in two restricted matrices; Silica sol-gel matrix and silica-ethylene glycol (EG) hybrid matrix (modified sol-gel matrix) with different concentrations to produce transparent silica xerogel Eu samples having no cracking and to select the optimum concentration which then doped with different concentrations of ZnO (as sensitizer) via modified sol-gel method to produce Eu composite zinc oxide. The concentration 2.5wt% was detected as optimum concentration of Eu3+and 0.625% wt for ZnO in modified sol-gel matrix. The compositional dependences of Judd–Ofelt and laser parameters of Eu3+ ions in studied matrices were evaluated and discussed. The FTIR spectrum of the prepared restricted samples was recorded and all structural changes in the samples prepared have been studied. The experimental dipole strengths were calculated from the areas under the absorption bands. The evaluated Judd-Ofelt parameters (Ωλ), using the observed spectral intensities, have been used to calculate various laser parameters viz., spontaneous emission probability (A), radiative life time (τ), fluorescence branching ratio (β) and stimulated emission cross section (σp). The effects of EG and ZnO on optical and lasing parameters of the samples were also discussed.