Methodology of Synthesis and Optical Analysis of Rare-Earth Ions (RE$^{3+})$ in the Polymeric Host PMMA

We report the syntheses of RE$^{3+}$:Y$_{2}$O$_{3}$ nanoparticles in the polymeric host, PMMA (Poly-Methyl Methacrylate). Addition of adequate amount of surfactant, named Hexadecyl Trimethyl Ammonium Bromide (CTAB) prevents the aggregation of nanoparticles in PMMA. The hydrophobic tails of CTAB micelles link to the hydrocarbon chains of PMMA, forming aggregates which trap the nanoparticles at those positions, thereby giving rise to a uniform distribution of nanoparticles in the polymer-surfactant matrix. Room temperature and the low temperature absorption spectra of various rare-earth samples have been obtained and included for detailed comparison. The Judd-Ofelt intensity parameters, radiative decay rates, branching ratios, and the corresponding radiative lifetimes of excited states are reported. The detailed analysis emphasizes the relevance of embedding the RE$^{3+}$:Y$_{2}$O$_{3}$ ions in the PMMA host.