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arXiv · 2011.11931

Quantum chaos driven by long-range waveguide-mediated interactions

Alexander V. Poshakinskiy·Janet Zhong·Alexander N. Poddubny
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Abstract

We study theoretically quantum states of a pair of photons interacting with a finite periodic array of two-level atoms in a waveguide. Our calculation reveals two-polariton eigenstates that have a highly irregular wave-function in real space. This indicates the Bethe ansatz breakdown and the onset of quantum chaos, in stark contrast to the conventional integrable problem of two interacting bosons in a box. We identify the long-range waveguide-mediated coupling between the atoms as the key ingredient of chaos and nonintegrability. Our results provide new insights in the interplay between order, chaos and localization in many-body quantum systems and can be tested in state-of-the-art setups of waveguide quantum electrodynamics.

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Alexander V. Poshakinskiy, Janet Zhong, Alexander N. Poddubny. 2020-11-24. Quantum chaos driven by long-range waveguide-mediated interactions. https://doi.org/10.1103/physrevlett.126.203602

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