Spectroscopic properties of LaAlO3:Tm3+ nanocrystals

LaAlO3 samples doped with thulium ions were prepared by the sol-gel method. The samples were annealed at 800 and 1100 °C. The sizes of the nanocrystals were 28 and 70 nm for the 800 and 1100 °C sample, respectively. Nanocrystals with 0.5 wt %, 3 wt%, 5 wt%, 7 wt% of Tm3+ were investigated by the spectroscopic means, for comparison data obtained for LaAlO3: Tm3+ single crystal was shown. Absorption, emission, and emission decay times were measured at room temperature in the IR, visible and near UV range. The difference in absorption and emission spectra and luminescence decay time determined by the methods of preparation and size of the samples are investigated.