DUAL-SIDE CHANNEL SPR BASED PHOTONIC CRYSTAL FIBER SENSOR

Abstract

Anovel dual-core photonic crystal fiber (PCF) sensor is designed to mimic visible and near-infrared regimes through the utilization of surface plasmon resonance (SPR). The sensor design aims to achieve wide refractive index (RI) sensing capabilities and simultaneous detection of multiple analytes. The PCF design features two concentric rings forming the cladding in a circular lattice configuration, strategically omitting air holes on both sides adjacent to the metal layer to enhance coupling effects. To induce plasmon resonance, a chemically inert thin layer of gold is applied to the half-ellipse shaped sensing channels. Utilizing the finite element method in COMSOL Multiphysics, we systematically explore the optical characteristics of suggested SPR based PCF. Operating within visible band, sensor demonstrates the ability to simultaneously detect multiple analytes within the range of 1.35-1.44. Furthermore, it exhibits a wider RI sensing range from 1.15 to 1.44 in the near-infrared(n-IR) band. The sensor showcases a wavelength sensitivity of 1840 nm/RIU and an amplitude sensitivity of 168.13 RIU−1 with a resolution of 6.71 × 10−5 RIU in the n-IR band. Conversely, in visible band, the sensor demonstrates higher sensitivity, reaching up to 4520 nm/RIU, and an amplitude sensitivity of 1093.29 RIU−1 with a resolution of 5.43 × 10−5 RIU. These findings underscore the potential of the dual-core SPR based PCF sensor for versatile and high-performance applications in RI sensing and multi-analyte detection for visible and near-infrared spectroscopy