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Simultaneous near-field and far field spatial quantum correlations in spontaneous parametric down-conversion

E. Brambilla·A. Gatti·M. Bache·L. A. Lugiato
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Abstract

We study the spatial correlations of quantum fluctuations that can be observed in multi-mode spontaneous parametric down-conversion in the regime of high gain. A stochastic model has been solved numerically to obtain quantitative results beyond the stationary plane-wave pump approximation. The pulsed shape of the pump beam and other features of the system, such as spatial walk-off and diffraction are taken into account. Their effect on the spatial quantum correlations predicted by the plane-wave pump theory is investigated, both for near field and far field measurements, in a type I and in a type II phase-matching configuration.

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E. Brambilla, A. Gatti, M. Bache, L. A. Lugiato. 2003-06-17. Simultaneous near-field and far field spatial quantum correlations in spontaneous parametric down-conversion. https://doi.org/10.1103/physreva.69.023802

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