Low loss flat dispersive hexagonal porous core THz fiber

Abstract A low loss porous core hexagonal lattice photonic crystal fiber (PCF) is proposed. Design procedure and properties are investigated in terahertz (THz) band. We explore different important properties of the PCF to evaluate the merit of proposed design. Circular air hole at the center surrounded by rectangular air hole array in the fiber core is designed in such a way that maximizes the core porosity of the fiber. The structure of cladding, on the other hand, is designed with a large hexagonal air hole array with tiny isolation width, resulting in a minimum total loss. The bulk material loss is diminished by 85.8% using core porosity of 80%. Numerical result shows relatively low confinement loss at 1 THz with flattened dispersion. Withal, single-mode propagation is exhibited in the proposed PCF design. The novel approach of this proposed PCF is unique to ensure good confinement in the core with a reasonable amount of power fraction.