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arXiv · 2504.21754

Virtual Atom-Photon Bound States and Spontaneous Emission Control

Stefano Longhi
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Abstract

In waveguide quantum electrodynamics systems, atomic radiation emission is shaped by the photonic environment and collective atom interactions, offering promising applications in quantum technologies. In particular, atom-photon bound states, inhibiting complete spontaneous decay of the atom, can be realized through waveguide dispersion engineering or by utilizing giant atoms. While steady-state bound states are well understood, transient or virtual bound states remain less explored. Here we investigate transient atom-photon bound states, arising from initial atom-photon entanglement, and propose methods to slow down spontaneous atomic decay.

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Stefano Longhi. 2025-04-30. Virtual Atom-Photon Bound States and Spontaneous Emission Control. https://doi.org/10.1364/ol.561740

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