Surface plasmon resonance structures in spectral interrogation using high refractive index prism materials for sensing of different amino acids

Abstract

A prism coupler-based nano-plasmonic sensor consisting of a high refractive index (RI) prism (2S2G-prism, LASF9-prism), gold (Au) metal film, and different amino acids as the dielectric sample is used for sensing in attenuated total internal reflection mode. An additional semiconductor (silicon) nano-layer over the gold surface has been used for increasing the stability and sensitivity of the surface plasmon resonance sensor. A comparative analysis of performance of the nano-plasmonic sensors in the spectral regime using these two high RI prism materials with an additional semiconductor nano-layer has been presented. The sensing performance of the proposed nano-plasmonic sensors in terms of evanescent field enhancement, spectral sensitivity, detection accuracy, figure of merit, and Q-factor with different amino acid samples has been discussed along with supporting theoretical simulations in a MATLAB® environment.