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arXiv:2106.09423 · Physical Review Letters

Dimerization of Many-Body Subradiant States in Waveguide Quantum Electrodynamics

A. V. Poshakinskiy, Alexander N. Poddubny

Published Oct 18, 2021• 30 citations
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Abstract

We theoretically study subradiant states in an 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 the 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.

DOI
10.1103/physrevlett.127.173601

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