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arXiv · 2312.17732

Photon liquefaction in time

Eduardo Zubizarreta Casalengua·Elena del Valle·Fabrice P. Laussy
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Abstract

We provide a mechanism to imprint local temporal correlations in photon streams which have the same character as spatial correlations in liquids. Usual single-photon emitters correspond, in this picture, to a (temporal) gas while uncorrelated light is the ideal gas. We argue that good single-photon sources are those that exhibit such temporal liquid features, i.e., with a plateau for their short-time correlations (as opposed to a linear dependence) and oscillations at later times, which is a direct manifestation of photon time-ordering. We obtain general, closed-form analytical expressions for the second-order coherence function of a broad family of "liquid light" which can be arbitrarily correlated, though never completely crystallized.

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Eduardo Zubizarreta Casalengua, Elena del Valle, Fabrice P. Laussy. 2023-12-29. Photon liquefaction in time. https://doi.org/10.1063/5.0206213

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