Microfluidic-Integrated Gold-Coated SPR Photonic Crystal Fiber for Refractive Index Sensing with Machine Learning-Based Analysis
摘要
A highly sensitive photonic crystal fiber (PCF) refractive index (RI) sensor based on surface plasmon resonance (SPR) has been proposed and evaluated numerically. The sensor features a solid silica core embedded within a periodic air-hole structure and microchannels coated in gold to improve plasmonic coupling. Numerical analysis using the finite element method (FEM) indicates that the sensor exhibits a clear redshift in resonance wavelength as the analyte RI goes up. Over the RI range of 1.37–1.42, it achieves a maximum sensitivity of 2800 nm/RIU and a resolution of 3.5 × 10− 5 RIU. The suggested sensor’s small size and excellent sensitivity make it ideal for advanced biological, chemical, and environmental monitoring. The results of the SPR-based PCF RI sensor are predicted through comparative analysis of several machine learning models, such as Support vector regression, Random Forest regression, and Extreme gradient boosting approaches.