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Title: Dicke superradiance in ordered arrays of multilevel atoms
In fully-inverted atomic ensembles, photon-mediated interactions give rise to Dicke superradiance, a form of many-body decay that results in a rapid release of energy as a photon burst. While originally studied in point-like ensembles, this phenomenon persists in extended ordered systems if the inter-particle distance is below a certain bound. Here, we investigate Dicke superradiance in a realistic experimental setting using ordered arrays of alkaline earth(-like) atoms, such as strontium and ytterbium. Such atoms offer exciting new opportunities for light-matter interaction as their internal structure offers the possibility of trapping at short interatomic distances compared to their strong long-wavelength transitions, providing the potential for strong collectively modified interactions. Despite their intricate electronic structure, we show that two-dimensional arrays of these atomic species should exhibit many-body superradiance for achievable lattice constants. Moreover, superradiance effectively ''closes'' transitions, such that multilevel atoms become more two-level like. This occurs because the avalanche-like decay funnels the emission of most photons into the dominant transition, overcoming the single-atom decay ratios dictated by their fine structure and Zeeman branching. Our work represents an important step in harnessing alkaline-earth atoms as quantum optical sources and as dissipative generators of entanglement.  more » « less
Award ID(s):
2112663
PAR ID:
10432474
Author(s) / Creator(s):
Date Published:
Journal Name:
arXivorg
Volume:
2304.00093
ISSN:
2331-8422
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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