Third-harmonic generation (THG) in silicon nitride waveguides is an ideal source of coherent visible light, suited for ultrafast pulse characterization, telecom signal monitoring and self-referenced comb generation due to its relatively large nonlinear susceptibility and CMOS compatibility. We demonstrate third-harmonic generation in silicon nitride waveguides where a fundamental transverse mode at 1,596 nm is phase-matched to a TM02 mode at 532 nm, confirmed by the far-field image. We experimentally measure the waveguide width-dependent phase-matched wavelength with a peak-power-normalized conversion efficiency of 5.78 × 10−7 %/W2 over a 660-μm-long interaction length.

中文翻译：

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氮化硅波导中相位匹配的三次谐波产生


氮化硅波导中的三次谐波产生 (THG) 是相干可见光的理想光源，由于其相对较大的非线性磁化率和 CMOS 兼容性，适用于超快脉冲表征、电信信号监测和自参考梳状产生。我们演示了氮化硅波导中的三次谐波产生，其中 1,596 nm 的基横模与 532 nm 的 TM02 模相位匹配，这一点已由远场图像证实。我们通过实验测量了波导宽度相关的相位匹配波长，在 660 μm 长的相互作用长度上峰值功率归一化转换效率为 5.78 × 10−7 %/W2。