(1. College of Software Engineering，Zhengzhou University of Light Industry, Zhengzhou 450001, China) (2. Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Electronic and Information Engineering, Xian Jiaotong University, Xian 710049, China) (3. Key Laboratory of Grain Information Processing and Control of the Ministry of Education, College of Information Science and Engineering, Henan University of Technology, Zhengzhou 450001, China)
Acoustic metamaterials as an emerging field of research in recent years, have greatly expanded the application of acoustic materials in various fields. Acoustic metasurfaces, a branch of acoustic metamaterials, have also received extensive attention from both domestic and foreign researchers. Acoustic metasurface composed of an array of metamaterial structural units based on sub-wavelength dimension is a new type of acoustic metamaterial. It can use the generalized Snell‘s law to achieve certain directional control of reflected or transmitted sound wave, and it has the unique advantage of using sub-wavelength thickness to control sound wave. Due to its simple structure, rich and unique physical characteristics, and flexible, effective control of acoustic wave, it has become a hot topic in the research of metamaterials. This article first introduced the concept of metasurface, then the design method of common structural units and the physical controlling mechanism of acoustic wave to realize negative refraction, sound focusing and asymmetric sound transmission based on folded space metasurface, pentamode metasurface and unstructured metasurface were elaborated in detail. Finally, the future problems related to the acoustic metasurface were discussed briefly, hoping to provide valuable information for the future study.