Au-TiO 2 coated dielectric micro-channel based plasmonic refractive index sensor

Due to their characterization of miniaturization, high sensitivity, and multiparameter estimation, plasmonic photonic crystal fiber (PCF) sensors have been exploited by researchers for refractive index (RI) sensing and biosensing with different types of PCF. This study introduces a surface plasmon resonance (SPR)-based microchannel PCF with square air hole sensor that may be used to detect a wide range of analyte RIs. A noble metal of gold Au with titanium dioxide TiO 2 that used to adhesive the metal which deposited on dielectric microchannel to generate plasmonic surface waves. The sensor can perform very well with analyte (n a ) of 1.34–1.41. The sensing analysis is investigated by the Comsol Multiphysics program based on the finite element method (FEM). The sensor displays maximum resolution, wavelength and amplitude sensitivity of 10 × 10 –5 RIU, 6500 nm/RIU, − 1641.78 RIU −1 , respectively. Moreover, figure of merit (FOM) is 207.08 × 10 –3 dB/RIU. Because of the optimized parameters of the proposed sensor, it can detect chemical and biomolecular targets.