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arXiv · 2504.02358

Interference trapping of populations in a semi-infinite coupled-resonator waveguide

Qinglian Fu·Jing Li·Jing Lu·Zhihui Peng·Lan Zhou
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Abstract

We study the energy structure and dynamics of a two-level emitter (2LE) locally coupled to a semi-infinite one-dimensional (1D) coupled-resonator array (CRA). The energy spectrum in the single-excitation subspace features a continuous band with scattering states, discrete levels with bound states, and a quantum phase transition characterized by the change of the number of bound states. The number of bound states is revealed by the behavior of the excited-state population at long times with quantum beat, residual oscillation, a constant with either non-zero or zero.

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Qinglian Fu, Jing Li, Jing Lu, Zhihui Peng, Lan Zhou. 2025-04-03. Interference trapping of populations in a semi-infinite coupled-resonator waveguide. https://arxiv.org/abs/2504.02358

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