The modern paradigm of functional new materials involves engineering structural units with specific functions to control their macroscopic performance, a concept that applies across a wide range of material science disciplines, from dynamic wave manipulation to low-dimensional quantum systems. These functional units overcome the elemental limitations of natural materials, thereby broadening the potential for designing and developing new materials with groundbreaking and transformative properties. For instance, the concept of metamaterials, initially developed for electromagnetics, has since found wide-ranging applications in controlling the propagation of dynamic waves, including acoustic waves in fluids, elastic waves in solids, and surface water waves. Over the past decade, research in this field has made significant strides, evolving from the study of negative-index metamaterials and transformation optics to the exploration of cutting-edge topics like novel wave manipulation using metasurfaces and topological materials. This special topic aims to further advance the field of functional metamaterials by exploring new theoretical concepts, innovative design strategies, cutting-edge experimental implementations, and novel devices and applications.

Sincerely,

Huangyang Chen, Xiamen University, E-mail: kenyon@xmu.edu.cn

Minghui Lu, Nanjing University, E-mail: luminghui@nju.edu.cn

Yangyang Fu, Nanjing University of Aeronautics and Astronautics, E-mail: yyfu@nuaa.edu.cn