Numerical simulation on the performance analysis of a graphene-coated optical fiber plasmonic sensor at anti-crossing

A graphene-based surface plasmon resonance sensor using D-shaped fiber in anti-crossing has been designed. Silver as a plasmon active metal is followed by graphene, which helps in preventing oxidation and shows better adsorption efficiency to biomolecules. A wavelength interrogation technique based on the finite element method has been used to evaluate performance parameters. Design parameters such as thickness of silver, residual cladding, and GeO₂ dopant concentration have been optimized. The wavelength sensitivity is found to be 6800  nm/RIU and resolution of 8.05×10^-5  RIU. We believe that usage of graphene on silver may open a new window for study of online biomolecular interaction.