Spider web-shaped photonic crystal fiber for THz wave propagation

A spider web-shaped terahertz photonic crystal fiber (PCF) is proposed. The transmission characteristics of the proposed PCF in the terahertz band areinvestigated based on the finite element method (FEM) by adjusting and optimizing the fiber structure parameters. The influences of the frequency, the core diameter, and the porosity on the transmission characteristics are deeply analyzed. Extremely low transmission losses can be achieved within the single mode transmission range of 0.6–1.2 THz, including the effective material loss (0.058 cm−1), the confinement loss (3.22 × 10-6 dB/cm), and the bending loss (9.73 × 10-11 cm−1).Additionally, the flat dispersion is as low as 0.075 ± 0.016 ps/THz/cm. At the same time, the fabrication technology of the proposed PCF is studied more thoroughly and systematically. This research can be suitable for long distance and high performance transmission of terahertz waves duo to its ultra low loss and flat dispersion.