Acoustic metamaterials, enabled by artificially engineered microstructures, have introduced fundamentally new concepts for the development of advanced acoustic materials and provide disruptive solutions to low-frequency noise control that cannot be achieved using conventional materials. This presentation will introduce our recent research on the fundamental principles, material development, and engineering applications of acoustic metamaterials.

First, we have established the phononic band theory of acoustic metamaterials, providing new theoretical foundations for tailoring effective acoustic parameters and manipulating the propagation and absorption of sound waves. By introducing highly symmetric artificial structures, we developed acoustic topological insulators, discovered the acoustic quantum spin Hall effect, established the band theory of acoustic topological insulators, and created a series of acoustic topological materials, thereby opening up the emerging field of topological acoustics.

Second, through the introduction of multiscale resonant units and their short- and long-range coupling, we developed an inverse-design methodology that enables on-demand optimization of the operating frequency and bandwidth of sound-absorbing materials. This approach has led to the development of lightweight, ultra-thin, low-frequency broadband sound-absorbing materials, overcoming one of the most challenging bottlenecks in broadband low-frequency noise control.

Finally, these acoustic metamaterials have been successfully applied in a wide range of engineering scenarios, providing effective solutions to noise-control challenges in major industrial systems—including large commercial aircraft, high-speed railways, ultra-high-voltage power stations, and coal-fired power plants—where conventional acoustic materials have proven inadequate.

Prof. Yanfeng Chen is a Member of the Chinese Academy of Sciences (CAS), Professor and Doctoral Supervisor at the State Key Laboratory of Solid Microstructures and the Department of Materials Science and Engineering, Nanjing University. He is a Changjiang Distinguished Professor appointed by the Ministry of Education of China and a recipient of the National Science Fund for Distinguished Young Scholars.

Prof. Chen serves as a Divisional Associate Editor (DAE) of Physical Review Letters (PRL) and as Vice Chair of the Metamaterials Committee of the Chinese Materials Research Society.

He has published more than 300 SCI-indexed papers in leading journals, including Physical Review Letters, Nature Physics, Nature Materials, Nature Communications, and Science. He has been recognized as a Clarivate Highly Cited Researcher. He holds 40 authorized Chinese invention patents and 4 U.S. patents. His honors include the Second Prize of the National Natural Science Award of China (2015) and the Ye Qisun Physics Award of the Chinese Physical Society (2012–2013).