Energy transfer mechanism between Ce and Tb ions in sol-gel synthesized YSO crystals

CHIRIU, DANIELE;STAGI, LUIGI;CARBONARO, CARLO MARIA;CORPINO, RICCARDO;RICCI, PIER CARLO

2016-01-01

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Abstract

The luminescence properties of Tb and Ce in Rare Earth Doped crystalline oxides largely depend on their relative concentrations: by increasing the dopant concentration, the luminescence profile changes from blue to green because of the energy transfer among centers. The kinetic properties of the luminescence of optically excited Terbium-Cerium co-doped Y2SiO5 sol-gel synthesized crystal powders have been investigated as a function of the Tb dopant concentration (Ce content fixed at 1% atomic). The interaction among different Tb emitting centers and their relation with Ce centers was explained within the Inokuti-Hirayama model for a dipole-dipole energy transfer mechanism in the low-middle Tb concentration range whilst the Forster-Dexter model was applied in the middle-high Tb concentration range. The kinetic model allows elucidating the role of sensitizer and activator ion as a function of Tb concentration, successfully estimating the energy transfer mechanism efficiency and calculating the critical Tb concentration.