Novel fiber Bragg grating assisted plasmon-polariton for bio-medical refractive-index sensors

A theoretical model for a novel refractive index fiber sensor based on the specific properties of the surface plasmon-polariton (SPP) is proposed and comprehensively investigated. The main principle of operation of this new device is based on the energy transfer between the fiber waveguide mode and the SPP provided by a properly designed short-period fiber Bragg grating imprinted into a waveguide fiber layer of a specially designed optical fiber. The waveguide layer is a dielectric layer of the fiber with the highest refractive index. Our simulations are based on coupled mode theory and performed for telecom wavelength range.