Ultra-Low Loss and Flat Dispersion Circular Porous Core Photonic Crystal Fiber for Terahertz Waveguiding

A novel design of circular porous core photonic crystal fiber (CCPCF) is proposed and studied for Terahertz propagation with an ultra-low-loss. The effective index, effective mode area, dispersion, material and bending losses of the suggested design are studied using full vectorial finite element method. The CCPCF with high cladding air filling factor and porous core exhibits ultra-low material absorption loss of 0.022 cm-1 at a frequency of 1.0 THz. Further, very low bending losses of 2.2×10-18 cm-1 can be achieved for 1.0 cm bending radius at 1.0 THz with low confinement loss of 1.37×10-5 cm-1. Additionally, an ultra-flat low dispersion of 0.61 ± 0.035 ps/THz/cm can be obtained within the frequency range of 0.8-1.0 THz. Therefore, the reported CCPCF has a strong potential for transmission in the Terahertz regime.