Subwavelength nanostructures made of high-index low-loss materials have revolutionized the fields of linear and nonlinear nanophotonics, stimulating growing demands for efficient and inexpensive fabrication technologies. Here, we demonstrate high-precision and reproducible printing of hemispherical Si nanoparticles (NPs) via controllable dewetting of glass-supported $\alpha$-Si films driven by a single femtosecond laser pulse. The diameter of the formed nanocrystalline NPs can be fully controlled by initial $\alpha$-Si film thickness as well as lateral size of the laser spot and can be predicted by a simple empirical model based on conservation of energy and mass. A resonant optical response associated with Mie-type resonances supported by hemispherical NPs was confirmed by combining numerical modeling with optical microspectroscopy. Inexpensive and high-performing direct laser printing of nanocrystalline Si Mie resonators with a user-defined arrangement opens a pathway for various applications in optical sensing and nonlinear nanophotonics.

中文翻译：

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激光印刷半球形硅Mie谐振器

由高折射率低损耗材料制成的亚波长纳米结构彻底改变了线性和非线性纳米光子学领域，刺激了对高效，廉价制造技术的日益增长的需求。在这里，我们演示了通过可控的单个飞秒激光脉冲驱动的玻璃支撑$ \ alpha- Si薄膜的可润湿性，可以对半球形Si纳米颗粒（NPs）进行高精度且可重现的印刷。形成的纳米晶纳米粒子的直径可以通过初始$ \ alpha $完全控制-Si膜厚度以及激光光斑的横向尺寸，可以通过基于能量和质量守恒的简单经验模型进行预测。通过将数值模型与光学显微光谱相结合，证实了与半球NPs支持的Mie型共振相关的共振光学响应。具有用户定义的排列方式的纳米晶Si Mie谐振器的便宜且高性能的直接激光印刷为光学传感和非线性纳米光子学中的各种应用打开了一条途径。