基于振幅和相位共同调控的声学超构表面的构建、机理及应用研究

As an ultrathin version of metamaterials, acoustic metasurfaces are constructed by arranging micro-structured artificial elements in a plane. Due to efficient manipulation on amplitude or phase of acoustic waves, researches on metasurfaces have become a promising and hot topic in the field of acoustic metamaterials. Based on the generalized acoustic Snell’s law, most of the previous acoustic metasurfaces are only focused on the phase modulation, leading to the critical limitations such as single modulation object, deficient working principle, and simply functionality. In order to overcome such limitations and expand the modulation abilities, in this proposed project we will carry out theoretical analysis, numerical simulations and experiments to systematically and thoroughly investigate the acoustic metasurfaces with simultaneous manipulation on amplitude and phase. First, we will build the physical models of various micro-structured elements, and design the elements with independently tailored acoustic effective parameters to construct metasurfaces. Second, a general design scheme of acoustic metasurfaces will be explored based on the Huygens’ principle. To achieve simultaneous manipulation of amplitude and phase, we will investigate the influence of the acoustic effective parameters on the inherent characters of acoustic waves. Based on these manipulation effects, we will develop new ultrathin acoustic functional devices for the applications of acoustic holography, acoustic computing, Fourier acoustics, etc. The proposed project features rich and meaningful significance both in academic research and engineering applications.

声学超构表面是由人工微结构单元在面内排列而成的超薄超构材料体系，它可在亚波长尺度上对声波振幅或相位等进行丰富、高效的调控，已成为声学超构材料的研究重点之一。已有的声学超构表面大多基于广义Snell定律对声波相位进行调控，因此存在调控对象单一、工作机理匮乏、声学功能简单等局限。为解决这些问题并拓展超构表面对声场的调控能力，本项目拟从理论分析、数值仿真和实验验证等方面，对基于振幅和相位共同调控的声学超构表面进行系统深入的研究：（1）建立微结构单元的有效物理模型，研究等效声学参数可独立调节的微结构单元，以构建超构表面；（2）基于惠更斯原理建立超构表面的普适模型，研究超构表面的等效声学参数对声波各参数的影响规律，实现对声波振幅和相位的共同调控；（3）基于超构表面的调控性质构建超薄新原理声学器件，研究其在声全息、声计算、傅立叶声学等方面的应用。本项目研究工作既富有学术意义，又具有较高的应用价值。

声学超构表面是由人工微结构单元在面内排列而成的超薄超构材料体系，它可在亚波长尺度上对声波振幅或相位等进行丰富、高效的调控，已成为声学超构材料的研究重点之一。已有的声学超构表面大多基于广义Snell定律对声波相位进行调控，因此存在调控对象单一、工作机理匮乏、声学功能简单等局限。为解决这些问题，本项目从理论分析、数值仿真和实验验证等方面，对声学超构表面和超构材料进行了系统而深入的研究。取得的研究成果包括：1）基于振幅和相位共同调控型超构表面实现了声学模拟计算器件。2）在零折射率超材料引入矩形缺陷对声透射率进行任意调控，实现了如全反射、全透射、声隐身等效应。3）基于声学超构表面实现了一种地毯式声隐身斗篷。4）研究了PT对称型零折射率超构材料的声散射，实现了如单向透明、激光/相干完美吸收、双向透明等效应。5）基于声学超构表面生成两束自弯曲波束，并干涉形成针状聚焦声场。6）基于Kagome声子晶体，实现了一种弹性波高阶拓扑绝缘体，观察到了鲁棒的拓扑边界态和角态。本项目研究的实施，明确了超构表面对声波振幅和相位的共同调控机理，并构建了多种性能奇特的超薄新原理声学器件。本项目研究工作既富有学术意义，又在声学模拟计算、声开关、隔声、声隐身、声吸收、声聚焦、声波导等领域具有广阔的应用价值。. 在项目研究期间，在SCI源刊物上发表论文12篇，国际学术会议口头报告2篇。申请国家发明专利1项，获授权国家发明专利1项。