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arXiv · 2311.09669

Degenerate spontaneous parametric down-conversion in nonlinear metasurfaces

Tetsuyuki Ochiai
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Abstract

We propose a simple scheme of degenerate spontaneous parametric down-conversion (SPDC) in nonlinear metasurfaces or photonic crystal slabs with quasi-guided modes. It employs a band crossing between P- and S-polarized quasi-guided mode bands inside the light cone and a selection rule in the conversion efficiency of the SPDC. The efficiency can be evaluated fully classically via the inverse process of noncollinear second-harmonic generation (SHG). As a toy model, we study the SPDC and SHG in a monolayer of noncentrosymmetric spheres and confirm that the scenario works well to enhance the SPDC.

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Tetsuyuki Ochiai. 2023-11-16. Degenerate spontaneous parametric down-conversion in nonlinear metasurfaces. https://arxiv.org/abs/2311.09669

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