基于超表面的远场多波束调控综述

超表面作为二维的的超材料,在保留其对电磁波调控能力的同时,具有剖面低、损耗小、易与其它器件集成的优点。自广义斯涅耳定律被提出以来,传统由透镜和棱镜等光学元件沿传播路径逐渐积累的相变方式开始被离散相位取代,极大地提升了超表面设计的灵活性。通过对超表面局部幅度和相位信息进行调控,可以改变入射波的传输方向,使其朝着不同方向传播。文章首先简要概述几种实现多波束激发的超表面平台,然后介绍了基于超表面平台对远场波束多波束调控的前沿进展,并对未来发展方向进行了展望。

Overview of Multi-beam Modulation Based on Metasurfaces

As a two-dimensional metamaterial, metasurfaces have the advantages of low profile, low loss and easy integration with other devices, while retaining the ability to manipulate electromagnetic waves. Since the concept of phase discontinuities and the generalized laws of reflection and refraction were proposed, metasurfaces become an alternative for traditional lens based on gradual accumulation along the wave path. By adjusting the local amplitude and phase information of the metasurface, incident wave can be transmitted in different directions. Firstly, a brief overview of several metasurface platforms for achieving multi beam excitation is provided. Then the frontier developments in far-field multi-beam modulation are introduced. Finally, the future development directions is prospected.