电磁超表面的物理和应用

Metamaterials (MTM) are artificial electromagnetic (EM) materials composed by subwavelength microstructures （meta-atoms）arranged in certain Macroscopic “orders”. Based on simple meta-atoms (e.g., single-mode symmetrical resonators) and simple orders (e.g., homogeneous or periodic), MTMs have already been thoroughly studied in the past decade and great achievements were obtained. Recently, several groups include our own have found that MTMs (particularly meta-surfaces) based on multi-freedom complex meta-atoms and special macroscopic orders exhibit even stronger abilities to manipulate EM waves. However, currently this kind of research is still at an initial stage, in which the theoretical models are too simple and experimental investigations are still under development, and how the multi-freedom coupling inside the complex meta-atoms and the macroscopic order govern the physical rules of the EM wave’s properties still remain unclear. Facing this grand challenge, here we propose to systematically study the physical properties of meta-surfaces based on complex meta-atoms and special macroscopic orders and their abilities to manipulate EM waves, through combining theory, numerical simulations, micro- and nano-fabrications, and experimental characterizations. In particular, we will conduct the following three parts of research: 1) Studies on electromagnetic properties of the complex meta-atom with multiple degrees of freedom; 2) Wave manipulations based on meta-surfaces constructed with special macroscopic order; 3) Applications of such meta-surfaces.

电磁超构材料是将亚波长微结构（即人工原子）按一定宏观排列组合而成的复合介质，前期基于单模对称型简单人工原子及均匀/周期型简单排列方式构建的超构材料在取得巨大成就的同时也碰到了瓶颈和挑战。近期人们（含申请人团队）发现基于多自由度耦合复杂“人工原子”及特殊宏观排列方式（如梯度，旋转性质）构建的超表面展现出对电磁波更强大的调控能力。然而此类研究目前尚处于的起步阶段，缺乏对复杂“人工原子”中多模式耦合效应及体系宏观排列方式与电磁波传播规律之间内在关联的深刻理解。针对上述重大挑战，我们将结合理论、仿真、样品制备及实验测试，研究基于复杂“人工原子”和特殊宏观排列方式构建的超表面体系的物性及对电磁波的调控，并发掘其实际潜力。为此我们将开展以下研究：1. 多自由度耦合的复杂人工原子的电磁响应研究；2. 基于特殊宏观排列方式的超表面对电磁波的调控研究；3. 电磁超表面的应用研究。

超构表面对电磁波的调控研究是微纳光子学和超构材料领域的研究前沿。本项目针对当前超构表面研究缺乏对复杂“人工原子”中多模式耦合效应及体系宏观排列方式与电磁波传播规律之间内在关联的深刻理解等挑战，展开了深入系统的研究，取得以下几方面的代表性研究成果：：1）建立了基于第一性原理的开放体系耦合模理论，为实现具有特定电磁辐射特性的复合型人工原子体系奠定了理论基础；2）揭示了超构表面角度色散的物理根源，提出实现自由调控超构表面角度色散的新方法；3）建立了基于多维度超构表面实现高效复杂矢量光场的新方法；4）基于复合型超构表面实现了手性解锁的高效多功能电磁功能调控；5）基于二维材料构建了动态可调超构表面；6）基于超构表面实现了对光和物质相互作用的高效调控。.在本项目支持下，团队发表SCI论文60 篇，其中包括Light：Science & Applications 5篇，Physical Review Letters 5篇，Nature Communication 2篇，Advanced Science 2篇， PhotoniX 1篇，Advanced Photonics 2篇，Nano Letter 1篇，Advances in Optics and Photonics 1篇等高影响力论文，申请国家发明专利8项（4项获得授权），主办国际学术会议1次，应邀35次在国际和国内学术会议上做邀请报告，培养博士研究生10人。本项目部分研究成果已经与实际应用相结合，解决了军民应用方面的实际问题..项目负责人周磊教授于2019年入选美国光学学会会士，2019-2022年入选ESI全球高被引学者。团队“超构表面对电磁波的调控”项目于2019年获得国家自然科学二等奖。