Plasmonic Coating on Chemically Treated Optical Fiber Probe in the Presence of Evanescent Wave: a Novel Approach for Designing Sensitive Plasmonic Sensor

Abstract

A new approach has been proposed for monolayer plasmonic coating on optical fiber for sensor application. It uses evanescent wave in addition to chemical linker while the chemically treated probe is dip-coated with nanoparticles. The combined technique for monolayer coating on optical fiber increases the packing density of the particles. Formation of densely packed nanoparticle monolayer leads to higher transmission loss and wavelength shifts which is used as surface plasmon resonance-based refractive index sensor. As a proof of the concept, we have prepared a similar probe which has been used as chemical sensor. The sensor significantly improves sensitivity due to increase in packing density and surface area. The sensitivity of the sensor depends upon the formation of the nanoparticle coating. We have demonstrated the probe sensitivity as 987.85 nm/RIU using commonly available chemicals.