Enhancement in figure of merit of silver-gold bimetallic surface plasmon resonance sensor

Abstract

In this work, a high figure of merit (FOM) surface plasmon resonance (SPR) with bimetallic layer (Au/Ag) based on wavelength and angular combined interrogations approach is presented. To further addition the performance of the SPR sensor, the sum of the minimum reflectivity (R_min) is calculated with the refractive index interval of 0.004 as a step from 1.33 to 1.37 at first. Then, the performance of the sensor is analyzed for varying silver-gold thickness. Our simulations indicate that the proposed configuration for Kretschmann’s SPR sensor should be silver (48 nm)-gold (1 nm) for achieving the best FOM (about 150 RIU^-1).