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arXiv · 2106.09423

Dimerization of many-body subradiant states in waveguide quantum electrodynamics

Alexander V. Poshakinskiy·Alexander N. Poddubny
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Abstract

We study theoretically subradiant states in the array of atoms coupled to photons propagating in a one-dimensional waveguide focusing on the strongly interacting many-body regime with large excitation fill factor $f$. We introduce a generalized many-body entropy of entanglement based on exact numerical diagonalization followed by a high-order singular value decomposition. This approach has allowed us to visualize and understand the structure of a many-body quantum state. We reveal the breakdown of fermionized subradiant states with increase of $f$ with emergence of short-ranged dimerized antiferromagnetic correlations at the critical point $f=1/2$ and the complete disappearance of subradiant states at $f>1/2$.

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Alexander V. Poshakinskiy, Alexander N. Poddubny. 2021-06-17. Dimerization of many-body subradiant states in waveguide quantum electrodynamics. https://doi.org/10.1103/physrevlett.127.173601

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