A key challenge for optical circuits is the ability to integrate nonlinear optical signal processing components such as optical modulators and frequency mixers at the chip scale. Optical antennas that focus light into nanoscale volumes can be utilized to shrink the footprint and increase the efficiency of these components. Multiresonant antennas that enhance both optical absorption and emission process are recently demonstrated to enable efficient nonlinear frequency conversion at the nanoscale and are promising as structures for second harmonic generation (SHG) and upconversion. Here, the ability of colloidal metasurfaces fabricated by self‐assembly as on‐chip platforms for enhanced SHG is demonstrated. These metasurfaces exhibit high spatial overlap of multiple surface plasmon modes whose frequencies can be independently tuned through appropriate design of colloidal and metasurface geometries. It is demonstrated that these bottom‐up structures rival lithographic nonlinear optical antennas in SHG efficiency, suggesting the potential for these colloidal metasurfaces in integrated on‐chip architectures.

中文翻译：

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双共振胶体超表面中增强的第二谐波产生

光电路的关键挑战是在芯片级集成非线性光信号处理组件（如光调制器和混频器）的能力。可以利用将光聚焦到纳米级体积的光学天线来缩小占地面积并提高这些组件的效率。最近证明了增强光吸收和发射过程的多谐振天线可以实现纳米级的高效非线性频率转换，并有望作为二次谐波生成（SHG）和上变频的结构。在此，展示了通过自组装制造的胶体超表面作为增强SHG的片上平台的能力。这些超表面表现出多个表面等离振子模式的高度空间重叠，其频率可通过适当设计的胶体和超表面几何形状进行独立调整。事实证明，这些自下而上的结构在SHG效率上可与光刻非线性光学天线相媲美，这表明这些胶体超表面在集成片上架构中的潜力。