Enhanced upconversion based on surface plasmon resonance in a multilayered UCNPs-metamaterial absorber

In this paper, we proposed a multilayer Metamaterial Absorber (MA) to enhance the up-conversion emission, which consists of silver grating, Up Conversion Nanoparticles (UCNPs) and silver film. Numerical and theoretical analysis results showed that tremendous up conversion enhancement is achieved at three wavelengths due to the surface plasmon resonance. Moreover, it was found that the interaction between the silver grating and the silver film is critical to the up-conversion enhancement. Tuning the thickness of the silver grating, the maximum enhanced factor (EFups) of 980 nm is 4 6.5 10⁴. This metamaterial absorber provided a novel approach in enhancing up conversion, and the research findings could be helpful to the design of biosensor and photovoltaic devices.