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arXiv · 2301.07441

Modeling the space-time correlation of pulsed twin beams

Alessandra Gatti·Ottavia Jedrkiewicz·Enrico Brambilla
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Abstract

Entangled twin-beams generated by parametric down-conversion are among the favorite sources for imaging-oriented applications, due their multimodal nature in space and time. However, a satisfactory theoretical description is still lacking. In this work we propose a semi-analytic model which aims to bridge the gap between time-consuming numerical simulations and the unrealistic plane-wave pump theory. The model is used to study the quantum correlation and the coherence in the angle-frequency domain of the parametric emission, and demonstrates a $g^{{1/2}} $ growth of their size as the gain $g$ increases, with a corresponding contraction of the space-time distribution. These predictions are systematically compared with the results of stochastic numerical simulations, performed in the Wigner representation, of the full model equations: an excellent agreement is shown even for parameters well outside the expected limit of validity of the model.

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Alessandra Gatti, Ottavia Jedrkiewicz, Enrico Brambilla. 2023-01-18. Modeling the space-time correlation of pulsed twin beams. https://arxiv.org/abs/2301.07441

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