论文标题
各向异性第二次谐波产生来自单晶金片
Anisotropic Second Harmonic Generation From Monocrystalline Gold Flakes
论文作者
论文摘要
具有明确定义的晶体学取向的贵族金属构成了一类吸引人的材料，用于控制纳米级的光结合相互作用。非线性光学过程对各向异性特别敏感，是纳米光学设备中结晶度的天然和通用探针。在这里，我们研究了单晶金片的非线性光学响应，揭示了{111}表面的第二谐波产生的极化依赖性，而多晶膜中明显不存在。除了提出一种在等离子系统中非线性响应方向增强的方法外，我们预计我们的发现可以用作一种快速且无损的方法，用于表征晶体质量和取向的方法，这在未来的应用中可能非常重要。
Noble metals with well-defined crystallographic orientation constitute an appealing class of materials for controlling light-matter interactions on the nanoscale. Nonlinear optical processes, being particularly sensitive to anisotropy, are a natural and versatile probe of crystallinity in nano-optical devices. Here we study the nonlinear optical response of monocrystalline gold flakes, revealing a polarization dependence in second-harmonic generation from the {111} surface that is markedly absent in polycrystalline films. Apart from suggesting an approach for directional enhancement of nonlinear response in plasmonic systems, we anticipate that our findings can be used as a rapid and non-destructive method for characterization of crystal quality and orientation that may be of significant importance in future applications.
