Surface plasmon resonance sensor of silver film based on Kretchmann configuration

Abstract

Performance of a surface plasmon resonance (SPR) sensor based on Kretchmann configuration for silver (Ag) film is evaluated via theoretical simulation. The film thickness and incident angle are varied to obtain the SPR wavelength in the range of 500-550 nm. Shift of SPR wavelength with refractive index of the dielectric defines the sensitivity whereas the resolution is obtained from the ratio of the instrumental resolution to the sensitivity. The SPR sensor shows increasing sensitivity for thicker film however the absorption magnitudes of such films are high and unfavourable for data acquisition. Film thickness of 45 nm and 50 nm which has good sensitivity and resolution with high absorbance magnitude of the SPR wavelength is the best thickness to be employed for sensing purpose.