Acoustic metasurfaces provide unprecedented flexibility for high-resolution acoustic field reconstruction, especially revolutionizing high-quality acoustic holographic display through their considerable spatial bandwidth product, which is a natural result of deep-subwavelength footprint of coding units of metasurfaces. However, conventional acoustic metasurfaces suffer from their static responses, therefore, reconfigurable coding units or switchable functionality of acoustic metasurfaces intrigue new trend in this field. In this talk, I will report my recent research progresses on reconfigurable coding units based on the concept of acoustic geometric-phase metasurfaces, and further demonstrate multi-channel acoustic holographic display by leveraging spatial manipulations (e.g., rotation, dislocation, spatial addressing, and order of arrangement) as an available degree of freedom in cascaded metasurfaces system. Either pixel-level reconfigurability or multi-channel coding-decoding scheme efficiently resolve the programmable acoustic holography via metasurface platform, which facilitates their potential applications in ultrasonic imaging and underwater wireless communications.

Bingyi Liu received the B. S. degree in Optical Information Science and Technology, the Ph. D. degree in Optics from Harbin Institute of Technology, Harbin, China, in 2014, and 2020, respectively. From 2021 to 2022, he was a postdoctoral fellow in the Beijing Institute of Technology and University of Paderborn (funded by CSC-DAAD Postdoctoral Scholarship). Currently, he is working as associate professor in Hefei University of Technology, Hefei, China. His research interests include acoustics, acoustic vortex, and acoustic metasurface and its application in underwater imaging and wireless communications. To date, Bingyi Liu has published more than 50 papers in the field of metamaterials and metasurfaces, received citation over 1500 times.