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Accurate switching intensities and length scales in quasi-phase-matched materials

Ole Bang·Torben Winther Graversen·Joel F. Corney
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Abstract

We consider unseeded Type I second-harmonic generation in quasi-phase-matched (QPM) quadratic nonlinear materials and derive an accurate analytical expression for the evolution of the average intensity. The intensity-dependent nonlinear phase mismatch due to the QPM induced cubic nonlinearity is found. The equivalent formula for the intensity for maximum conversion, the crossing of which changes the nonlinear phase-shift of the fundamental over a period abruptly by $π$, corrects earlier estimates by more than a factor of 5. We find the crystal lengths necessary to obtain an optimal flat phase versus intensity response on either side of this separatrix intensity.

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Ole Bang, Torben Winther Graversen, Joel F. Corney. 2001-01-30. Accurate switching intensities and length scales in quasi-phase-matched materials. https://doi.org/10.1364/ol.26.001007

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