arXiv:2012.03735 · Physical Review A

Photon-photon correlations from a pair of strongly coupled two-level emitters

Elnaz Darsheshdar, Mathilde Hugbart, Romain Bachelard, Celso J. Villas-Bôas

Published May 6, 2021• 14 citations

Abstract

We investigate two-color photon correlations in the light emitted by two strongly driven, strongly interacting two-level emitters. The correlations are interpreted introducing the collective dressed states picture, which allows us to describe both bunching and antibunching based on the allowed and prohibited transitions. At odds from weakly interacting emitters, the strong interaction lifts the degeneracy of the energy differences between the different states, leading to a temporal breaking of symmetry for the correlations: photons of different frequencies may not be emitted in any order. Finally, we show that most of the virtual processes, which involve pairs of photons, yield nonclassical correlations when the sum of their energies fits any of the interaction-induced sidebands in the emitted spectrum. In particular, depending on the frequency of the emitted photons, correlations strong enough to violate Bell inequalities can appear.

DOI: 10.1103/physreva.103.053702

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