arXiv:2310.19115 · Physical Review A

Photon bound states in coupled waveguides

Björn Schrinski, Johan A. Brimer, Anders Søndberg Sørensen

Published Oct 2, 2024• 2 citations

Abstract

Photon bound states have been identified as particular solutions to the scattering of two photons from a single emitter, but from these results the full nature of these states remains elusive. We study a novel, clear and unambiguous signature that these bound states are truly bound. To this end we consider a new configuration of close-by waveguides, each chirally coupled to two-level emitters. We show that in this system the photon bound states behave like rigid molecules, where photons do not tunnel individually but rather collectively, such that there is rarely a single photon in each waveguide. We further identify new classes of bound states in this system.

DOI: 10.1103/physreva.110.l041701

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