Absorption intensities and emission cross section of intermanifold transition of Er3+ in Er3+:Y2O3 nanocrystals

The room temperature absorption intensities of Er3+(4f11) transitions in synthesized Er3+:Y2O3 nanocrystals have been analyzed using the Judd-Ofelt (J-O) model in order to obtain the phenomenological intensity parameters. The J-O intensity parameters are subsequently used to determine the radiative decay rates, radiative lifetimes, and branching ratios of the Er3+ transitions from the upper multiplet manifolds to the corresponding lower-lying multiplet manifolds LJ2S+1 of Er3+(4f11). The emission cross section of the important intermanifold Er3+ I13∕24→I15∕24 (1.5μm) transition has been determined. The room temperature fluorescence lifetime of this transition in Er3+:Y2O3 nanocrystals was measured. From the radiative lifetime determined from the J-O model and measured fluorescence lifetime, the quantum efficiency of this material was determined. The comparative study of Er3+(4f11) ions suggests that synthesized Er3+:Y2O3 nanocrystals could be an excellent alternative to single crystal Er3+:Y2O3 for certain applications especially in the near infrared region.