Single-mode condition and dispersion of terahertz photonic crystal fiber

Abstract

We have investigated properties of a plastic photonic crystal fiber guiding terahertz radiations, THz photonic crystal fiber. The single-mode condition and dispersion of a plastic triangular THz photonic crystal fiber are investigated by using the plane wave expansion method and the beam propagation method. The THz photonic crystal fiber can perform as a single-mode fiber below 2.5 THz when the ratio of diameter (d) and period (A) of air holes is less than 0.475. The THz photonic crystal fiber with Lambda = 500 mu m and d/Lambda = 0.4 shows almost zero flattened dispersion behavior, -0.03 +/- 0.02 ps/THz center dot cm, in the THz frequency range from 0.8 to 2.0 THz.