Numerical Demonstration of Photonic Quasi-Crystal Fiber–Surface Plasmonic Resonance Urinary Methanol Sensor

This article demonstrates simple germanium-doped solid-core photonic quasi-crystal fiber (PQF) for biochemical sensing applications. The chemically stable thin gold film and eightfold rhombic triacontahedron photonic quasi-crystal structure subsumed in the improved external sensing approach using the finite element method (FEM) tool. The optimized rhombic PQF structure was numerically developed using 14,862 finite mesh elements. The FEM analysis shows high wavelength and amplitude sensitivity, low confinement loss, good figure of merit, high detection accuracy, and reasonable resolution at the refractive index (RI) values from 1.32 to 1.36. Based on the results, this unique rhombic PQF structure has advantages in the high sensitivity with low loss and ease of fabrication among the existing PQF and photonic crystal fiber sensors in biochemical sensing applications.