Environmental Sensitivity of Fabry-Perot Microcavities Induced By Layered Graphene-Dielectric Hybrid Coatings

TL;DR

This paper introduces a fiber-based environmental sensor utilizing layered graphene-dielectric coatings, demonstrating enhanced sensitivity to liquid media refractive index changes through both theoretical modeling and experimental validation.

Contribution

It presents a novel sensor design with layered graphene-dielectric coatings and validates its high sensitivity through transfer matrix analysis and experimental testing.

Findings

Enhanced sensitivity of reflection phase shift to liquid media refractive index.

Successful experimental demonstration with graphene oxide/polyethylenimine multilayers.

Cost-effective production method for hybrid coatings suitable for real-world sensors.

Abstract

We propose a fiber-based environmental sensor that exploits the reflection phase shift tunability provided by the use of layered coatings composed of dielectric slabs spaced by conducting membranes. A transfer matrix study is done in a simplified theoretical model, for which an enhanced sensitivity of the reflection interference pattern to the output medium is demonstrated, in the typical refractive index range of liquid media. An experimental configuration using a cascaded Fabry-Perot microcavity coated by a graphene oxide/polyethylenimine (GO/PEI) multilayered structure is demonstrated. Its cost effective chemical production method makes graphene oxide-based hybrid coatings excellent candidates for future real-life sensing devices.