Optical materials are undergoing revolutionary transformations driven by nanotechnology. Our ability to engineer structures at a scale smaller than the wavelength of light enables new properties and functionalities otherwise not available in natural bulk optical materials. A class of such components—dielectric metasurfaces—employs two-dimensional arrays of designer resonant nanoscale elements whose optical response is defined by their geometry. While linear regimes of interactions between dielectric metasurfaces and moderately intense light have already formed a mature field of applied research and engineering, new frontiers are being actively explored in the nonlinear optical regime describing interactions of metasurfaces with strong optical fields. In this Research Update, we cover the most recent progress along with several directions of research within the field of nonlinear optics of dielectric metasurfaces. Specifically, we review approaches to design and fabricate metasurfaces with high local field enhancements that facilitate nonlinear light–matter interactions, outline nonlinearity-enabled functionalities of dielectric metasurfaces, explore resonant metasurfaces in the strong-field non-perturbative regime, and discuss the implications of the time-variant refractive index in metasurfaces that interact with strong optical fields produced by laser pulses.

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强光场中的共振介电超表面

光学材料正在经历纳米技术驱动的革命性变革。我们能够以小于光波长的尺度设计结构，从而实现了天然大块光学材料所不具备的新特性和功能。一类这样的组件——电介质超表面——采用二维阵列设计的谐振纳米级元件，其光学响应由它们的几何形状定义。虽然介电超表面和中等强度光之间相互作用的线性机制已经形成了一个成熟的应用研究和工程领域，但非线性领域正在积极探索新的前沿领域。描述超表面与强光场相互作用的光学机制。在本研究更新中，我们介绍了最新进展以及介电超表面非线性光学领域的几个研究方向。具体来说，我们回顾了设计和制造具有高局部场增强的超表面的方法，这些超表面促进了非线性光-物质相互作用，概述了介电超表面的非线性功能，探索了强场非微扰状态下的共振超表面，并讨论了与激光脉冲产生的强光场相互作用的超表面中随时间变化的折射率。