Ahmad Mohammadi

In this study, the sensitivity of photon crystal fiber biosensor based on surface plasmon containing graphene has been investigated. The designed photonic crystal fiber structure consists of a central air cavity around which the holes are arranged in a hexagonal arrangement. Despite two air cavities at the top and bottom of the hexagon and a defect in the structure, an asymmetry is created in the photonic crystal fiber, which can be used to concentrate electromagnetic waves in certain parts of the structure and also increase the surface plasmon intensification. The presence of a gold layer around the photon crystal fiber has added plasmonic properties to the fiber. Adding a layer of graphene prevents the oxidation of gold and improves the sensing performance of the biosensor. In this research, finite element method and comsol software have been used to evaluate the sensitivity of the biosensor. In addition, the existing parameters have been optimized to achieve the best possible structure. According to the information obtained, the maximum spectral sensitivity in the wavelength range of 850-500 nm in the photonic crystal fiber structure designed for analyte refractive index is 1.35 times (nm / RIU) 4000 and the amplitude sensitivity (1 / RIU) is 75.07. This study showed that due to the simple designed structure, it is possible to build it experimentally and in comparison with complex structures, spectral sensitivity is very good.