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arXiv · 1007.3825

Stationary entanglement in N-atom subradiant degenerate cascade systems

Massimo Borrelli·Nicola Piovella·Matteo G. A. Paris
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Abstract

We address ultracold $N$-atom degenerate cascade systems and show that stationary subradiant states, already observed in the semiclassical regime, also exist in a fully quantum regime and for a small number of atoms. We explicitly evaluate the amount of stationary entanglement for the two-atom configuration and show full inseparability for the three-atom case. We also show that a continuous variable description of the systems is not suitable to detect entanglement due to the nonGaussianity of subradiant states.

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Massimo Borrelli, Nicola Piovella, Matteo G. A. Paris. 2010-07-22. Stationary entanglement in N-atom subradiant degenerate cascade systems. https://doi.org/10.1103/physreva.83.013621

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