Impact of plasmonic nanoparticles on up-conversion luminescence and efficiency of erbium-doped ceria nanoparticles under 780 nm excitation

Up-conversion process is being widely studied due to its enormous applications such as bioimaging, energy harvesting, and optical sensors. However, the low conversion efficiency can limit these applications. In this paper, a detailed study about the effect of using plasmonic metallic nanostructures is presented, aiming to support the up-conversion process under 780 nm excitation. The targeted material is erbium-doped ceria material due to its promising optical properties along with the relatively low-phonon nature of ceria host. At an average distance of 0.67 nm between Er ions, the efficiency can be improved from 1.58% to 13.52% for green emission and from 0.007% to 0.234% for the red one, which corresponds to 30-fold and 8.5-fold, respectively. Also, some other parameters such as irradiance and multi-phonon relaxations and their impact on the efficiency, according to the added gold nanoparticles are studied. Such promising modeling results could help in further studies regarding the addition of metallic nanoparticles to improve the quantum conversion efficiency due to its plasmonic effect.