Enhanced upconversion luminescence using long-range surface plasmon resonance mode with prism coupler

In the study, we present the significant enhancement of the upconversion luminescence by taking advantage of long-range surface plasmon resonance mode. Compared with the reflection enhanced upconversion luminescence of Ag film, the intensity of upconversion luminescence enhanced by long-range surface plasmon resonance mode is improved 100 times. Additionally, the finite-difference time-domain simulation indicates that the incident light energy can concentrate in the upconversion nanoparticles doped dielectric layer at the long-range surface plasmon resonance mode, which the maximum electric field enhancement factor |E|2/|E0|2 can reach to 58. The experimental result shows that the upconversion luminescence enhancement is related to the thickness of doped Polymethylmethacrylate (PMMA) layer. Furthermore, due to the excited upconversion luminescence having high directionality, it is shown that the strong upconversion luminescence could be received at the specific angle.