Engineering photonic band gaps with a waveguide-QED structure containing an atom-polymer array

We investigate the generation and engineering of photonic band gaps in waveguide quantum electrodynamics systems containing periodically arranged atom polymers. We first consider the configuration of a dimer array coupled to a waveguide. The results show that if the intra- and intercell phase delays are properly designed, the center and the width of the band gaps, as well as the dispersion relation of the passbands, can be modified by adjusting the intracell coupling strength. These manipulations provide ways to control the propagating modes in the waveguide, leading to some interesting effects such as slowing or even stopping a single-photon pulse. Finally, we take the case of the tetramer chain as an example to show that, in the case of a larger number of atoms in each unit cell, tunable multigap structures and more sophisticated band-gap engineering can be realized. Our proposal provides efficient ways for photonic band-gap engineering in micro- and nanoquantum systems, which may facilitate the manipulation of photon transport in future quantum networks.