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arXiv · 1402.6915

Exact cascading nonlinearity in quasi-phase-matched quadratic media

Matteo Conforti
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Abstract

The evolution of light pulses and beams in a quasi-phase-matched (QPM) quadratic medium is usually described by considering only the spatial harmonic of the QPM grating that minimizes the residual phase-mismatch. I show that, for strongly phase-mismatched interactions (the cascading regime), several harmonics need to be accounted for in order to obtain the correct value of the effective cubic nonlinearity, of which I find a simple analytical expression. I discuss the effects of the higher order harmonics of the grating on solitary wave propagation.

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Matteo Conforti. 2014-02-27. Exact cascading nonlinearity in quasi-phase-matched quadratic media. https://doi.org/10.1364/ol.39.002427

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