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arXiv · 0812.3533

X-entanglement of PDC photon pairs

E. Brambilla·L. Caspani·O. Jedrkiewicz·L. A. Lugiato·A. Gatti
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Abstract

We investigate the spatio-temporal structure of the bi-photon entanglement in parametric down-conversion (PDC) and we demonstrate its non-factorable X-shaped geometry. Such a structure gives access to the ultra-broad bandwidth of PDC, and can be exploited to achieve a bi-photon temporal localization in the femtosecond range. This extreme localization is connected to our ability to resolve the photon positions in the source near-field. The non factorability opens the possibility of tailoring the temporal entanglement by acting on the spatial degrees of freedom of twin photons.

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E. Brambilla, L. Caspani, O. Jedrkiewicz, L. A. Lugiato, A. Gatti. 2008-12-18. X-entanglement of PDC photon pairs. https://arxiv.org/abs/0812.3533

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