Resonance-Related Coupling of Symmetric Dual-Core Hybrid Photonic Crystal Fibers

Dual-core hybrid photonic crystal fibers in which high-index inclusions are introduced between the two cores are proposed and the directional coupling characteristics of them are investigated numerically. Alternative cutoffs of even and odd supermodes, decoupling effect, and maxima of coupling length are presented. It is demonstrated that the resonance and location of the high-index inclusions play an important role.