论文标题
在等离子元面的表面晶格共振引起的第三个谐波产生的增强
Enhancement of third harmonic generation induced by surface lattice resonances in plasmonic metasurfaces
论文作者
论文摘要
我们研究了来自等离子体跨面的实验性第三次谐波产生（THG），这些谐波跨面由中心对称金纳米杆的二维矩形晶格组成。通过改变入射角和晶格周期，我们显示了在涉及波长处的表面晶格共振（SLR）是如何确定非线性效应幅度的主要贡献者。当我们在相同或不同频率下将多个SLR激发多个SLR时，会进一步提高THG。当发生这样的多个共振时，会观察到有趣的现象，例如沿跨表面进行反传播的表面波的最大THG增强，并模仿三阶非线性。
We investigate experimentally Third Harmonic Generation (THG) from plasmonic metasurfaces consisting of two-dimensional rectangular lattices of centrosymmetric gold nano-bars. By varying the incidence angle and the lattice period, we show how Surface Lattice Resonances (SLRs) at the involved wavelengths are the major contributors in determining the magnitude of the nonlinear effects. A further boost on THG is observed when we excite together more than one SLR, either at the same or at different frequencies. When such multiple resonances take place, interesting phenomena are observed, such as maximum THG enhancement for counter-propagating surface waves along the metasurface, and cascading effect emulating a third-order nonlinearity.
