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Entanglement and conservation of orbital angular momentum in spontaneous parametric down-conversion

S. P. Walborn·A. N. de Oliveira·R. S. Thebaldi·C. H. Monken
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Abstract

We show that the transfer of the plane wave spectrum of the pump beam to the fourth-order transverse spatial correlation function of the two-photon field generated by spontaneous parametric down-conversion leads to the conservation and entanglement of orbital angular momentum of light. By means of a simple experimental setup based on fourth-order (or two-photon) interferometry, we show that our theoretical model provides a good description for down-converted fields carrying orbital angular momentum.

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S. P. Walborn, A. N. de Oliveira, R. S. Thebaldi, C. H. Monken. 2005-03-02. Entanglement and conservation of orbital angular momentum in spontaneous parametric down-conversion. https://doi.org/10.1103/physreva.69.023811

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