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arXiv · 1506.08635

Temporal coherence and correlation of counterpropagating twin photons

Alessandra Gatti·Tommaso Corti·Enrico Brambilla
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Abstract

This work analyses the temporal coherence and correlation of counterpropagating twin photons generated in a quasi-phase matched nonlinear cristal by spontaneous parametric-down conversion. We find out different pictures depending on the pump pulse duration relative to two characteristic temporal scales, determined respectively by the temporal separation between the counter-propagating and the co-propagating wavepackets. When the pump duration is intermediate between the two scales, we show a transition from a highly entangled state to an almost separable state, with strongly asymmetric spectral properties of the photons.

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Alessandra Gatti, Tommaso Corti, Enrico Brambilla. 2015-06-29. Temporal coherence and correlation of counterpropagating twin photons. https://doi.org/10.1103/physreva.96.013820

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