Infrared induced red luminescence of Eu3+-doped polycrystalline LiNbO3
Résumé
Polycrystalline lithium niobate powders were prepared by the sol-gel method. Different grain sizes were obtained by controlling the annealing temperature. The Eu3+ ion was used as a luminescent probe of the nonlinear optical properties of the grains. Strong red emission deriving from Eu3+ ions was observed under pulsed infrared laser irradiation at 936.0nm due to absorption of the light produced in the second harmonic generation process. A measurable emission was observed only for grains having a size of the least 200nm, depending on the annealing temperature.