The simulating of optical sensor based on selective resonance coupling

Refractive index sensors are one of the most widely used sensors in the bioelectronics and optoelectronics industries. The use of materials and structures that can detect the refractive index of unknown materials has important applications in biochemistry and medical engineering. In this paper, a polymer-based dual-core photon crystal fiber is introduced to measure the refractive index of a fluid. The size of the holes of the analyte cores and the light-transmitting solid core are engineered to be able to pass the main single mode. Due to its cheapness, high mechanical ability and ease of fabrication, the photon crystal fiber substrate is made of PMMA polymer. After simulating the structure and using the existing mathematical relations and examining the diffusion modes, for the complete transfer of light from the solid core to the core of the analyte channel, a fiber length of 0.13 cm has been obtained. The simulation results show that for a refractive index of 1.44, a sensitivity value of 1000  and a detection limit can be achieved by this sensor. All simulation steps in the field of FDTD are obtained in Lumerical software.