Preparation and spectroscopic characterization of Nd3+:Y2O3 nanocrystals suspended in polymethyl methacrylate

We describe a method to fabricate polymethyl methacrylate (PMMA), a polymeric host, in which nanocrystals of Nd3+:Y2O3 are suspended. The spectroscopic properties of this material are analyzed using the standard Judd-Ofelt technique. The phenomenological Judd-Ofelt intensity parameters are used to calculate the radiative decay rates and the branching ratios of the F-4(3/2) -> I-4(J) (J = 9/2, 11/2, 13/2, and 15/2) intermanifold transitions. The room temperature fluorescence lifetime has been measured for the most intense F-4(3/2) -> I-4(11/2) emission transition. Emission cross sections for the intense intermanifold transitions and peak emission cross sections for the intense inter-Stark transitions are also reported. Assignments to individual Stark levels of the I-4(J) manifolds have been made and compared with the calculated splittings reported earlier. Finally, the spectroscopic properties of the Nd3+:Y2O3 nanocrystals suspended in PMMA are compared with those of Nd3+ doped in various host materials. Detailed optical analysis led to favorable values of fluorescence lifetime and emission cross section for the F-4(3/2) -> I-4(11/2) transition, which suggest that the Nd3+:Y2O3 nanocrystals embedded in PMMA would have potential for various photonic applications including laser systems and optical communication devices. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3122300]