Futuristic elongated-hexagonal photonic crystal waveguide for slow light

Abstract

The capability of photonic crystal waveguides (PCWs) to reduce the device footprint, extend the bandwidth, and control the group velocity dispersion effects, has prompted many researchers to propose new models of slow-light PCWs. An unpretentious figure of merit (FoM) to evaluate the intrinsic performances of slow-light structures, e.g., maximum buffer capacity and delay time with modest dispersion engineering, is the normalized-delay-bandwidth-product (NDBP). We proposed a unique platform from an elongated-hexagonal (e-hexagonal) lattice PCW for multi-modes and its performance has been investigated. The proposed e-hexagonal PCW has an ultra-wide bandwidth compatible with a high group index and a high FoM around 0.6456 within the flat band of slow light. We observed periodic oscillations in the field pattern of spatially confined light along the path of propagation, indicating a strong coupling among the cavities of defects. The e-hexagonal PCW is an outstanding initial point for further slow-light engineering in PCWs alongside a promising application for random-access memories and all-optical signal processors.