多维度超表面及其在信息加密防伪上的应用

超表面是一种厚度在亚波长或波长量级的人工层状材料。可通过调控超表面单元结构上的大小、形状、转角、位移量等自由度，实现对电磁波频率、振幅、相位、偏振等特性的灵活有效调控。超表面具有超薄、宽带、低损耗、易加工、灵活设计，功能强大等特点。文中综述了具有单维度、双维度、多维度光场调控功能的超表面及其在外部激励作用下具有主动可调特性超表面的发展历程，并特别介绍了这些超表面用于信息加密防伪领域的实现方式与优势特点。相比于传统的信息加密防伪技术，超表面信息加密防伪术具有亚波长像素，精密控制，安全系数高等特点，展现了全新视角，拥有广阔的发展前景。

Multi-dimensional metasurface and its application in information encryption and anti-counterfeiting

Metasurface is an artificial layered material with a subwavelength or wavelength-scale thickness. By adjusting the size, shape, orientation angle, displacement, etc. of the metasurface nanostructures, dimensions of electromagnetic wave including frequency, amplitude, phase, polarization, wavelength, etc. can be flexibly and effectively controlled. Metasurface has various characteristics including the ultra-thin thickness, broadband, low loss, easy processing, flexible design and powerful functionalities. This paper reviewed metasurfaces capable of one-dimensional, two-dimensional, multi-dimensional, and active light field manipulations and their applications in information encryption and anti-counterfeiting. An outlook was given for the future development trend of multi-dimensional metasurfaces. Compared with the traditional information encryption and anti-counterfeiting technology, the metasurface has the superior advantages in sub-wavelength pixels, precise controlling and ultra-secure factor in information encryption and anti-counterfeiting. Its bright future to replace the traditional information encryption and anti-counterfeiting technology was envisioned, and its broad application prospects were underpinned.