We report on the experimental observation of internally pumped parametric oscillation in a high-$\!Q$Q lithium niobate microresonator under conditions of natural phase matching. Specifically, launching near-infrared pump light around 1060 nm into a $ z $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 sidebands around the pump-the first steps of optical frequency comb generation via cavity-enhanced second-harmonic generation.

中文翻译：

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在χ（2）耳语画廊模式微谐振器中内部泵送参量振荡和二次梳状产生的实验观察。

我们报告了在自然相位匹配条件下在高Q Q Q铌酸锂微谐振器中内部泵送参数振荡的实验观察。具体来说，将1060 nm附近的近红外泵浦光发射到z切成z的全铌酸锂微谐振器中，我们观察到在第二谐波产生接近自然相位匹配的条件下，输入泵周围会产生光学边带。我们发现可以通过改变实验参数来产生各种不同的边带频移。在特定条件下，我们观察到泵周围几个边带的级联生成-光学频率梳的第一步是通过腔增强的第二谐波生成。