Oscillating bound states in a waveguide-QED system with two giant atoms
Phys. Rev. A 113, 053703 – Published 4 May, 2026
DOI: https://doi.org/10.1103/p67j-1r3b
Abstract
We study bound states in the continuum (BICs) in a system of two identical two-level giant atoms coupled to a one-dimensional waveguide. By deriving dark-state conditions, we clarify how coupling configurations and atomic parameters influence decay suppression. Through analysis of the long-time dynamical behavior of atoms and bound photons, we carry out a detailed classification of bound states and explore the connections between these dynamical behaviors and the system’s intrinsic light-matter interactions. The system supports static bound states with persistent atomic excitations, and oscillating bound states (OBSs) with periodic atom-photon or atom-atom excitation exchange. Under certain conditions, OBSs can contain more harmonic components owing to the emergence of additional quasidark modes, rendering them promising platforms for high-capacity quantum information processing. These findings advance the understanding of BICs in waveguide quantum electrodynamics with multiple giant atoms and reveal their prospective applications in quantum technologies.
