Modeling of Tapered Fiber-Optic Surface Plasmon Resonance Sensor With Enhanced Sensitivity

Theoretical model for surface-plasmon-resonance-based fiber-optic sensor with a metal-coated uniform core sensing region sandwiched between two identical tapered fiber regions is proposed. The effect of taper ratio (TR) on the sensitivity of the sensor is studied. The study shows that the proposed probe geometry with TR lying between 1.5 and 2.0 provides the best performance. The physical reasons behind sensitivity enhancement due to tapered regions are provided.