Dual-Aperture Dual-Core Photonic Crystal Fiber Sensor Based on Surface Plasmon Resonance

Surface plasmon resonance sensing, which is based on photonic crystal fiber sensing technology, has a broad spectrum of applications in the detection of pharmaceuticals, environmental pollution, and food safety. This investigation proposes a photonic crystal fiber optic sensor with two cores and two holes to address the issue of limited sensor sensitivity. The high sensitivity of the sensor is optimized by the dual-channel design, which minimizes energy loss and maximizes the coupling efficacy in SPP mode by increasing the contact area of the measured liquid. Concurrently, the plasma resonance process generates an increased amount of energy due to the dual-core architecture. Simulation results show that the sensor has a maximum wavelength sensitivity of 21,500 nm/RIU and a maximum theoretical resolution as high as 4.878 × 10⁻⁷ RIU in the refractive index detection range of 1.33–1.43 and thus is expected to be applied in the field of hematology detection.