arXiv:2001.00414 · Physical Review A

Single-photon scattering and bound states in an atom-waveguide system with two or multiple coupling points

Wei Zhao, Zhihai Wang

Published May 26, 2020• 158 citations

Abstract

In this paper, we investigate the single-photon scattering and bound states in a one-dimensional coupled-resonator waveguide which couples to a single artificial giant atom with two or more coupling points. When the atom couples to the waveguide via two resonators, the single-photon reflection rate is characterized by either Breit-Wigner or Fano lineshapes. When the atom couples to the waveguide via multiple resonators, we show numerically how the destructive interference effect leads to a complete single-photon reflection. We also find a phase-transition phenomena for the multiresonator coupling case, which reveals that the upper bound state only exists when the atom-waveguide coupling strength is above a critical value.

DOI: 10.1103/physreva.101.053855

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