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arXiv · 1709.05239

Quasi-phase-matching $\chi^{(3)}-$parametric interactions in sinusoidally-tapered waveguides

Mohammed F. Saleh
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Abstract

In this article, I show how periodically-tapered waveguides can be employed as efficient quasi-phase-matching schemes for four-wave mixing parametric processes in third-order nonlinear materials. As an example, a thorough study of enhancing third-harmonic generation in sinusoidally-tapered fibres has been conducted. The quasi-phase-matching condition has been obtained for nonlinear parametric interactions in these structures using Fourier-series analysis. The dependencies of the conversion efficiency of the third harmonic on the modulation amplitude, tapering period, longitudinal-propagation direction, and pump wavelength have been studied. In comparison to uniform waveguides, the conversion efficiency has been enhanced by orders of magnitudes. I envisage that this work can reshape the field of guided nonlinear optics using centrosymmetric materials.

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Mohammed F. Saleh. 2017-09-15. Quasi-phase-matching $\chi^{(3)}-$parametric interactions in sinusoidally-tapered waveguides. https://doi.org/10.1103/physreva.97.013850

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