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arXiv · 1410.6957

Frequency comb generation in quadratic nonlinear media

Iolanda Ricciardi·Simona Mosca·Maria Parisi·Pasquale Maddaloni·Luigi Santamaria·Paolo De Natale·Maurizio De Rosa
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Abstract

We experimentally demonstrate and theoretically explain the onset of optical frequency combs in a simple cavity-enhanced second-harmonic-generation system, exploiting second-order nonlinear interactions. Two combs are simultaneously generated around the fundamental pump frequency, with a spectral bandwidth up to about 10 nm, and its second harmonic. We observe different regimes of generation, depending on the phase-matching condition for second-harmonic-generation. Moreover, we develop an elemental model which provides a deep physical insight into the observed dynamics. Despite the different underlying physical mechanism, the proposed model is remarkably similar to the description of third-order effects in microresonators, revealing a potential variety of new effects to be explored and laying the groundwork for a novel class of highly efficient and versatile frequency comb synthesizers based on second-order nonlinear materials.

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Iolanda Ricciardi, Simona Mosca, Maria Parisi, Pasquale Maddaloni, Luigi Santamaria, Paolo De Natale, Maurizio De Rosa. 2015-06-03. Frequency comb generation in quadratic nonlinear media. https://doi.org/10.1103/physreva.91.063839

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