Optical Transmission Spectral Analysis of Ag/PS Spherical Arrays

Mono-layer spherical polystyrene particle (PS) arrays were prepared by a spin coating method, and then by combined use of vacuum vaporization technology, the Ag Nano-film coated PS spherical arrays were produced.A theoretical analysis shows that the optical transmission characteristics of the composite structure are decided by the whispering gallery mode (WGM) resonance and surface plasmon polaritons (SPPs) resonance.Compared with the experimental results, the transmission characteristics of a perfect model shows the full width half height value of the SPPs resonant peak is reduced and the peak undergoes a large red shift, which indicates a significant influence of the defects on the transmission spectrum.The research results may find potential application in enhancing the intensity of LED emission and improving the resolution of Raman spectra.