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arXiv · 2006.08106

Parametric down-conversion beyond the semi-classical approximation

Filippus S. Roux
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Abstract

Using a perturbative approach, we investigate the parametric down-conversion process without the semi-classical approximation. A Wigner functional formalism, which incorporates both the spatiotemproal degrees of freedom and the particle-number degrees of freedom is used to perform the analysis. First, we derive an evolution equation for the down-conversion process in the nonlinear medium. Then we use the perturbative approach to solve the equation. The leading order contribution is equivalent to the semi-classical solution. The next-to-leading order contribution provides a solution that includes the evolution of the pump field as a quantum field.

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Filippus S. Roux. 2020-06-15. Parametric down-conversion beyond the semi-classical approximation. https://doi.org/10.1103/physrevresearch.2.033398

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