We report an indium phosphide nanowire (NW)-induced cavity in a silicon planar photonic crystal (PPC) waveguide to improve the light–NW coupling. The integration of NW shifts the transmission band of the PPC waveguide into the mode gap of the bare waveguide, which gives rise to a microcavity located on the NW section. Resonant modes with Q factors exceeding 103 are obtained. Leveraging on the high density of the electric field in the microcavity, the light–NW interaction is enhanced strongly for efficient nonlinear frequency conversion. Second-harmonic generation and sum-frequency generation in the NW are realized with a continuous-wave pump laser in a power level of tens of microwatts, showing a cavity-enhancement factor of 112. The hybrid integration structure of NW-PPC waveguide and the self-formed microcavity not only opens a simple strategy to effectively enhance light–NW interactions, but also provides a compact platform to construct NW-based on-chip active devices.

中文翻译：

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光子晶体波导中的纳米线辅助微腔和启用的高效光频转换

我们报告了在硅平面光子晶体 (PPC) 波导中磷化铟纳米线 (NW) 诱导的腔，以改善光-NW 耦合。NW 的集成将 PPC 波导的传输带转移到裸波导的模式间隙中，从而产生位于 NW 部分的微腔。获得了 Q 因子超过 103 的谐振模式。利用微腔中电场的高密度，光-NW相互作用被强烈增强，以实现高效的非线性频率转换。NW中的二次谐波产生和和频产生是通过功率级为数十微瓦的连续波泵浦激光器实现的，腔增强因子为112。