Optimizing Chemical Sensing Performance: A New Terahertz Waveguide Plasmonic Sensor with Hybrid Refractive Index Integration

This article proposes photonic crystal fiber (PCF) with a square hollow-core sensor for detecting chemical substances effectively. COMSOL Multiphysics software is employed to investigate mentoring and detecting characteristics of the sensor using a finite element method (FEM) implementation. Rectangular air holes are used to reduce fabrication complexity. The suggested fiber is numerically examined in terahertz (THz) frequency spectrum from 1.8 to 2.5 THz to obtain superior sensitivity while minimizing confinement loss. The simulation result of this sensor exhibits higher relative sensitivity including benzene, ethanol, and water for 99.41%, 99.27%, and 98.95% with confinement loss (CL) as 1.80 × 10 −11 dB/m, 4.86 × 10 −12 dB/m, and 8.01 × 10 −13 dB/m respectively at 2.2 THz. This PCF also has a substantial EA of 8.08 × 10 −8 m 2 as well as a small EML of 0.0018 cm −1 at a frequency of 2.2 THz. Additionally, we anticipate that the highly recommended rectangular PCF design will be specifically useful for identifying chemical substances in the fields of material science, industry, nano-optics, biomedicine, and other THz technology communication sectors.