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arXiv · 2012.04113

Classification of three-photon states in waveguide quantum electrodynamics

Janet Zhong·Alexander N. Poddubny
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Abstract

We provide the first classification of three-photon eigenstates in a finite periodic array of two-level atoms coupled to a waveguide. We focus on the strongly subwavelength limit and show the hierarchical structure of the eigenstates in the complex plane. The main characteristic eigenstates are explored using entanglement entropy as a distinguishing feature. We show that the rich interplay of effects from order, chaos to localisation found in two-photon systems extends naturally to three-photon systems. There also exist interaction-induced localised states unique to three-photon systems such as bound trimers, corner states and trimer edge states.

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Janet Zhong, Alexander N. Poddubny. 2020-12-07. Classification of three-photon states in waveguide quantum electrodynamics. https://doi.org/10.1103/physreva.103.023720

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