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International Conference on Quantum Information

X-entanglement of PDC photon pairs

A. Gatti, Lucia Caspani, E. Brambilla, O. Jedrkiewicz, L.A. Lugiato

Published Jan 1, 2008• 0 citations
Publisher

Abstract

The X-wave picture is adopted to describe the spatio-temporal entanglement of PDC photons. Key elements of novelty are the non-factorability of the state and the extreme relative localization of photons in space and time.
DOI
10.1364/icqi.2008.qtub2

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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.