کنفرانس بین المللی میکروالکترونیک ایران

صفحه اصلی / هفتمین کنفرانس بین المللی میکروالکترونیک ایران

Numerical Modeling and Simulation of High Sensitivity Photonic Crystal Fiber Optical Sensors

نویسندگان :

Ali Asghar Molavi Choobini¹ Farkhonde Zamaninejad² Sara Sadat Ghaffari-Oskooei³

1- دانشگاه تهران 2- دانشگاه شهید بهشتی 3- دانشگاه الزهرا(س)

کلمات کلیدی :

Surface Plasmon Resonance (SPR)،Photonic Crystal Fiber (PCF)،Silver–Gold Hybrid Coating،Refractive Index Sensitivity،Biomedical Optical Sensing

چکیده :

In present study, a highly sensitive photonic crystal fiber (PCF)-based optical sensor is designed and analyzed for surface plasmon resonance (SPR) sensing applications. The proposed structure integrates a metallic layer—either pure silver or a hybrid silver–gold bilayer—at the interface between the silica core and the analyte region to excite surface plasmon polaritons (SPPs). A complete 2D numerical model is developed using the Wave Optics Module in COMSOL Multiphysics, accounting for dispersive refractive indices of the metallic and dielectric components via the Drude–Lorentz model. Mode analysis is conducted to compute the complex effective refractive index and evaluate modal field distributions and confinement loss across various wavelengths. Simulation results show that the silver-coated configuration yields sharper and stronger resonance due to enhanced field localization, achieving a maximum confinement loss near 550 nm. In contrast, the Ag+Au bilayer structure preserves high plasmonic performance while improving environmental stability. Both configurations demonstrate high refractive index sensitivity through resonance wavelength shifts, confirming the potential of the design for high-accuracy, label-free biochemical sensing in the visible spectral range.