Influence of Design Parameters on the Performance of a Surface Plasmon Sensor Based Fiber Optic Sensor

In the present work, the influence of two key design parameters, namely, fiber core diameter and sensing region length on the performance of a fiber optic surface plasmon resonance sensor, was experimentally observed. The sensor was designed with a multimode optical fiber of numerical aperture 0.40 and a thin silver layer of 50 nm thickness. The performance evaluation was carried out in terms of three performance parameters: sensitivity, signal-to-noise ratio and resolution. It was found that performance of the sensor tends to improve if fiber of large core diameter is used. Further, sensing region length should be taken as small as possible to attain highly sensitive and accurate sensing procedure. The experimental results are explained in terms of related physical background and mathematical expressions.