High-Order Nonlinear Spin-Orbit Interaction on Plasmonic Metasurfaces
High-Order Nonlinear Spin-Orbit Interaction on Plasmonic Metasurfaces
复制标题
等离激元超表面上的高阶非线性自旋轨道相互作用
DOI：
10.1021/acs.nanolett.0c03100
复制
发表时间：
2020-12-09
期刊：
影响因子：
10.8
通讯作者：
Zhang, Shuang
中科院分区：
文献类型：
--
作者：
Chen, Shumei;Li, Kingfai;Zhang, Shuang
在线性光学中，光的角动量可以很容易地通过结构化介质（如液晶、超颖表面和分叉光栅）中的光学自旋轨道相互作用（SOI）来操纵。类似地，超颖表面可以用于生成具有定制定义的自旋角动量（SAM）和轨道角动量（OAM）状态的非线性光束。然而，它已被限制到一个低阶的过程中，只有一个高斯形的基波被使用。在这项工作中，高阶非线性光学SOI效应的超颖表面上表现出通过产生多个角动量态的非线性波。这是通过利用由基波（FW）的SAM和OAM状态以及等离子体超表面的拓扑电荷提供的自由度来实现的。揭示了非线性波的本征和非本征贡献的机制。超颖表面上的高阶非线性SOI为实现超紧凑非线性涡旋光束提供了新的机会。
In linear optics, the angular momentum of light can be easily manipulated through the optical spin-orbit interaction (SOI) in structured media such as liquid crystals, metasurfaces, and forked gratings. Similarly, metasurfaces can be used to generate nonlinear optical beams with both custom-defined spin angular momentum (SAM) and orbital angular momentum (OAM) states. However, it has been limited to a low-order process in which only a Gaussian-shaped fundamental wave is used. In this work, the high-order nonlinear optical SOI effect on metasurfaces is demonstrated through the generation of multiple angular momentum states in nonlinear waves. This is achieved by exploiting the degrees of freedom provided by both the SAM and the OAM states of the fundamental wave (FW) and the topological charges of the plasmonic metasurfaces. The mechanism of both intrinsic and extrinsic contributions to the OAM of the nonlinear waves is revealed. High-order nonlinear SOI on metasurfaces offers new opportunities for realizing ultracompact nonlinear vortex beams.