Er$^{3+}$:Y$_{2}$O$_{3}$ Fluorescence Enhancement through Energy Transfer to Plasmonic Nanoparticles

Rare earth (RE) and noble metal (NM) hetero-nanostructures hold promise for many unique and robust applications. The overlap of the Er$^{3+}$ $^{4}$H$_{5/2}$ fluorescence manifold with the extinction spectra of the Au surface plasmons can give rise to energy transfer between Er$^{3+}$ (donor) and plasmonic Au (acceptor). In the limit of high efficiency energy transfer, the intensity of emission from the Er$^{3+}$/Au hetero-nanostructure becomes significantly more intense than the emission of Er$^{3+}$ alone. The quantum efficiency of the combined system, in the limit of high energy transfer, is dependent on only the scattering quantum efficiency of the Au nanoparticles. Additionally, this enhancement is a function of the quantity of gold attached. Here, we report and discuss the synthesis and spectroscopic properties of colloidal hetero-nanostructures based on a radiating plasmon model of surface plasmon coupled emission. This research was supported by the National Science Foundation PREM Grant No. DMR-0934218.