title: Wideband and low dispersion slow-light waveguide based on a photonic crystal with crescent-shaped air holes.
abstract: We present a procedure to generate slow light with a large group index, wideband, and low dispersion in our suggested photonic crystal waveguide. By modulation of the declinations in the first two rows of air holes, the group index, the bandwidth, and the dispersion can be tuned effectively. Utilizing the two-dimensional plane wave expansion method (PWE) and the finite-difference time-domain method (FDTD), we demonstrate slow light with the group indices of 23, 35, and 45, respectively, while restricting the group-index variation within a 10% range. We accordingly attain an available bandwidth of 40.7, 23.7, and 5.1 nm, respectively. Meanwhile, the normalized delay-bandwidth product stays around 0.45, with minimal dispersion less than 0.2 (ps2/m) for all the cases.
authors.affiliation: School of Physics and Microelectronic and Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Meng
authors.forename: Ling-ling
authors.initials: LL
authors.lastname: Wang
authors.forename: Wei-qing
authors.initials: WQ
authors.lastname: Huang
authors.forename: Xiao-fei
authors.initials: XF
authors.lastname: Li
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhai
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang