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arXiv · 1912.02804

Experimental observation of internally-pumped parametric oscillation and quadratic comb generation in a $\chi^{(2)}$ whispering-gallery-mode microresonator

Ian Hendry·Luke S. Trainor·Yiqing Xu·Stéphane Coen·Stuart G. Murdoch·Harald G. L. Schwefel·Miro Erkintalo
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Abstract

We report on the experimental observation of internally-pumped parametric oscillation in a high-Q lithium niobate microresonator under conditions of natural phase-matching. Specifically, launching near-infrared pump light around 1060 nm into a $z$-cut congruent lithium niobate microresonator, we observe the generation of optical sidebands around the input pump under conditions where second-harmonic generation is close to natural phase-matching. We find that a wide range of different sideband frequency shifts can be generated by varying the experimental parameters. Under particular conditions, we observe the cascaded generation of several equally-spaced sidebands around the pump -- the first steps of optical frequency comb generation via cavity-enhanced second-harmonic generation.

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Ian Hendry, Luke S. Trainor, Yiqing Xu, Stéphane Coen, Stuart G. Murdoch, Harald G. L. Schwefel, Miro Erkintalo. 2019-12-05. Experimental observation of internally-pumped parametric oscillation and quadratic comb generation in a $\chi^{(2)}$ whispering-gallery-mode microresonator. https://doi.org/10.1364/ol.385751

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