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arXiv · 1210.1366

Random quasi-phase-matched second-harmonic generation in periodically poled lithium tantalate

Salvatore Stivala·Alessandro C. Busacca·Alessia Pasquazi·Roberto L. Oliveri·Roberto Morandotti·Gaetano Assanto
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Abstract

We observe second harmonic generation via random quasi-phase-matching in a 2.0 μm periodically poled, 1-cm-long, z-cut lithium tantalate. Away from resonance, the harmonic output profiles exhibit a characteristic pattern stemming from a stochastic domain distribution and a quadratic growth with the fundamental excitation, as well as a broadband spectral response. The results are in good agreement with a simple model and numerical simulations in the undepleted regime, assuming an anisotropic spread of the random nonlinear component.

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Salvatore Stivala, Alessandro C. Busacca, Alessia Pasquazi, Roberto L. Oliveri, Roberto Morandotti, Gaetano Assanto. 2012-10-04. Random quasi-phase-matched second-harmonic generation in periodically poled lithium tantalate. https://doi.org/10.1364/ol.35.000363

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