PHOTONICS AND NANOSTRUCTURES-FUNDAMENTALS AND APPLICATIONS, vol.48, 2022 (SCI-Expanded)
We propose an asymmetric distribution of a hexagonal lattice for achieving near-zero group velocity with negative group delay. This study reports the effect of the continuous geometric perturbation on the photonic band diagram and consequently its impact on phase velocity, group velocity, and effective refractive index. We provide a promising method for modifying the photonic band diagram to obtain an exotic dispersion diagram. With this broadband spanning from the E band to the L band, the light pulse envelope travels with almost zero velocity and is promising for application in a wide variety of light-based devices.