Plasmonic enhancement of upconversion emission in Ag@NaYF4:Er3+/Yb3+ phosphor

Upconversion emission enhancement through different coating concentrations of silver nanoparticles (AgNPs) on NaYF4:Er3+/Yb3+ phosphor nanoparticles is shown. Surface plasmonic resonance effect enhances the upconversion emission at 522, 546 and 656 nm corresponding to 2H11/2 → 4I15/2, 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions, respectively.251