A rigorous analysis of the Plasmon-modes on a film metallic shell covering a step-index optical fiber

This paper investigates the plasmon modes (TM₀₁ polarized modes) in a step-index optical fiber coated by a thin metallic film, surrounded by a dielectric regions. This original Plasmon-modes modeling considers the core and cladding layers of the fiber as analysis components. The dispersion curves of the structure with silver film are figured out in function of the fiber parameters; core radius, cladding and film tickness. The results are essential to understand the core and cladding influences on the Plasmon-modes The validation of the developed modeling was confirmed by comparing the obtained results with those in, which analyse a weakly guided silica optical fiber coated by a thin silver metallic film. Situation, in which, the core and cladding are taked as a single region.