Wideband and low dispersion slow light by altering the geometry of a photonic crystal waveguide

In this paper, a novel type of slow light photonic crystal waveguide obtained by enlarging the entire holes of the PhC and shifting the first and second rows of the air holes adjacent to the waveguide center in the longitudinal direction, the designed structure provided a nearly constant group index over a large bandwidth. A flexible control of ng (18.24 < ng < 41.7) with large bandwidth (11.7 nm < Δλ < 24 nm) has been achieved. As well, a large normalized delay-bandwidth NDBP products ranging from 0.282 to 0.465 have obtained.