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arXiv · 2007.02949

Vacancy-like dressed states in topological waveguide QED

Luca Leonforte·Angelo Carollo·Francesco Ciccarello
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Abstract

We identify a class of dressed atom-photon states formingat the same energy of the atom at any coupling strength. As a hallmark, their photonic component is an eigenstate of the bare photonic bath with a vacancy in place of the atom. The picture accommodates waveguide-QED phenomena where atoms behave as perfect mirrors, connecting in particular dressed bound states (BS) in the continuum or BIC with geometrically-confined photonic modes. When applied to photonic lattices, the framework provides a general criterion to predict dressed BS in lattices with topological properties by putting them in one-to-one correspondence with photonic BS. New classes of dressed BS are thus predicted in the photonic Creutz-ladder and Haldane models. In the latter case, states with non-zero local photon flux occur, where an atom is dressed by a photon orbiting around it.

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Luca Leonforte, Angelo Carollo, Francesco Ciccarello. 2020-07-06. Vacancy-like dressed states in topological waveguide QED. https://doi.org/10.1103/physrevlett.126.063601

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