The guidance mechanism and numerical simulation of THz polymer hollow-core photonic crystal fiber

With the development of terahertz (THz) technology, an efficient propagation waveguide is essential for the construction of compact THz devices. Hollow core photonic crystal fiber with a large air core at the center and a cladding formed by a periodic arrangement of polymer tubes has been demonstrated in this paper. The guidance mechanism is based on anti-resonant reflection from struts of solid material in the cladding. Since most electromagnetic field is dominated in the air core, hollow core fibers have obvious advantages in lower absorption. The propagation characteristics of the fiber, such as the mode field distribution and the loss coefficient are numerically investigated through the finite element method. The result shows that an effective way to reduce the absorption is to enlarge the central air core and reduce the overlap between the field and material.