Design and numerical analysis of dual-core photonic crystal fiber-based biosensor

In this study, the coupling and the relative sensitivity characteristics of a Dual-Core Photonic Crystal Fiber (DC-PCF)-based liquid sensor are evaluated by employing the full-vectorial Finite element Method (FV-FEM). The simulation results demonstrate that coupling length of the proposed sensor varies between 2mm and 0.2mm length at wide wavelength range (800–1600 nm) for low index analytes (1.33–1.36). Besides, birefringence of order ≈ 10-4 is reported. It is found that analyte with 1.36 index reaches higher sensitivity levels. On the other hand, the coupling length of the proposed sensor can be optimized with the ellipticity ratio of the central core hole. Bending analysis on coupling length and optical power fluctuations is also reported. It is found that the power °ow in one core is increasing almost 90% towards the bending direction. The proposed structure with simple design parameters has a great potential in various biomedical applications including DNA detection and can also be employed as fibre-based refractometer in various sensing applications.