Analysis and design of terahertz photonic crystal fibers by an effective-index method

An effective-index method (EIM) is used to analyze and design photonic crystal fibers (PCFs) for the terahertz radiation. By building an analogy between a conventional optical fiber and a PCF, the EIM solves the effective index of the fiber cladding and the effective modal index of a PCF analytically. The EIM is first validated by comparison with available data in the reference, showing that the role of material dispersion is negligible at higher frequencies. Terahertz PCFs with flattened dispersion are designed based on this method and the scaling property of the Maxwell equations.