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arXiv · 0902.1660

Propagation of transverse intensity correlations of a two-photon state

D. S. Tasca·S. P. Walborn·F. Toscano·P. Pellat-Finet·P. H. Souto Ribeiro
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Abstract

The propagation of transverse spatial correlations of photon pairs through arbitrary first-order linear optical systems is studied experimentally and theoretically using the fractional Fourier transform. Highly-correlated photon pairs in an EPR-like state are produced by spontaneous parametric down-conversion and subject to optical fractional Fourier transform systems. It is shown that the joint detection probability can display either correlation, anti-correlation, or no correlation, depending on the sum of the orders $α$ and $β$ of the transforms of the down-converted photons. We present analytical results for the propagation of the perfectly correlated EPR state, and numerical results for the propagation of the two-photon state produced from parametric down-conversion. We find good agreement between theory and experiment.

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D. S. Tasca, S. P. Walborn, F. Toscano, P. Pellat-Finet, P. H. Souto Ribeiro. 2009-02-10. Propagation of transverse intensity correlations of a two-photon state. https://doi.org/10.1103/physreva.79.033801

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