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Temporal Dynamics of Photon Pairs Generated by an Atomic Ensemble

S. V. Polyakov·C. W. Chou·D. Felinto·H. J. Kimble
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Abstract

The time dependence of nonclassical correlations is investigated for two fields (1,2) generated by an ensemble of cold Cesium atoms via the protocol of Duan et al. [Nature Vol. 414, p. 413 (2001)]. The correlation function R(t1,t2) for the ratio of cross to auto-correlations for the (1,2) fields at times (t1,t2) is found to have a maximum value Rmax=292(+-)57, which significantly violates the Cauchy-Schwarz inequality R<=1 for classical fields. Decoherence of quantum correlations is observed over 175 ns, and is described by our model, as is a new scheme to mitigate this effect.

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S. V. Polyakov, C. W. Chou, D. Felinto, H. J. Kimble. 2004-06-08. Temporal Dynamics of Photon Pairs Generated by an Atomic Ensemble. https://doi.org/10.1103/physrevlett.93.263601

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