Surface Plasmon resonance implemented silver thin film PCF sensor with multiple – Hole microstructure for wide ranged refractive index detection

Abstract

This paper aims to demonstrate the sensing of different materials based on their refractive indices. The Surface Plasmon Resonance(SPR) phenomenon shown by Photonic Crystal Fiber(PCF) is proving to be quite useful among the sensor markets and thus, it becomes really important to design a flexible and affordable sensor of this kind with high sensitivity. SPR based PCF sensor with plasmonic material, silver embedded on it has been designed with the implementation of the Finite element method. We have modeled SPR sensors with multiple air holes and silica is the background material. The basic principle of using the analyte is that it binds the immobile molecules of silver to its own molecules which get mobilized in presence of the incident light and finally cause the variation of the refractive index. When the refractive indices of the analyte are varied from 1.25 to 1.30, a range of variation in the loss curves is seen. The core and Surface Plasmon Polaritons modes are matched based on their phases and it is done by plotting the refractive indices of core and SPP modes against the wavelength in µm along with the confinement loss against wavelength. The sensor that is obtained is highly sensitive with a wavelength sensitivity of around 1932.09 RIU−1. The resolution of the sensor is 3 × 10-5 RIU. On comparison with the literature, it is found that the sensitivity of the sensor so achieved is highly suitable for the detection purposes in the field of pharmacy and this Ag-based photonic crystal fiber sensor proves to be a revolutionary sensor in the field of biosensors.