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.
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Hydrodynamic superradiance in wave-mediated cooperative tunneling
Abstract Superradiance occurs in quantum optics when the emission rate of photons from multiple atoms is enhanced by inter-atom interactions. When the distance between two atoms is comparable to the emission wavelength, the atoms become entangled and their emission rate varies sinusoidally with their separation distance due to quantum interference. We here explore a theoretical model of pilot-wave hydrodynamics, wherein droplets self-propel on the surface of a vibrating bath. When a droplet is confined to a pair of hydrodynamic cavities between which it may transition unpredictably, in certain instances the system constitutes a two-level system with well-defined ground and excited states. When two such two-level systems are coupled through an intervening cavity, the probability of transition between states may be enhanced or diminished owing to the wave-mediated influence of its neighbour. Moreover, the tunneling probability varies sinusoidally with the coupling-cavity length. We thus establish a classical analog of quantum superradiance.
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- Award ID(s):
- 2154151
- PAR ID:
- 10415301
- Date Published:
- Journal Name:
- Communications Physics
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2399-3650
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s42005-022-00918-y
