Design and characterization of a photonic crystal fiber for improved THz wave propagation and analytes sensing

In this article, a hexagonal-shaped porous core and sectored-cladding structured photonic crystal fiber (PCF) is presented for efficient wave propagation in Terahertz (THz) domain. The full vector analysis based finite element method with Comsol software (v. 5.3a) is employed to design and optimize the PCF geometry and evaluate its optical properties. The PCF geometry demonstrates polarization maintaining attributes with a significant distinction between x and y polarization modes. The proposed PCF exhibits an ultra-low effective material loss of 0.013 cm−1 and 0.020 cm−1 in x and y polarization modes, respectively with a flattened dispersion of ± 0.020 ps/THz/cm and ± 0.065 ps/THz/cm in the respective modes at 1 THz. Additionally, the proposed PCF structure is investigated for sensing different liquid chemicals (cholesterol, methanol, ethanol, and benzene) and air pollutants (cyanide, dioxin, nitrogen oxide, and hydrogen sulfide). It is shown that the proposed PCF can outperform a number of recently reported designs in the literature. The fabrication potential of the PCF are also discussed in the context of present developments in manufacturing.