Topological acoustics is an emerging field that lies at the intersection of condensed matter physics, mechanical structural design and acoustics engineering. It explores the design and construction of novel artificial structures, such as acoustic metamaterials and phononic crystals, to manipulate sound waves robustly, taking advantage of topological protection. Early work on topological acoustics was limited to duplicating topological phases that have been understood in condensed matter systems, but recent advances have shifted to exploring new topological concepts that are difficult to realize in other physical systems, such as various topological semimetal phases, and topological phases associated with Floquet engineering, fragile topology, non-Hermiticity and synthetic dimensions. These developments demonstrate the unique advantages of topological acoustic systems and their role in developing topological physics. In this Review, we survey the fundamental mechanisms, basic designs and practical realizations of topological phases in acoustic systems and provide an overview of future directions and potential applications.

拓扑声学是凝聚态物理、机械结构设计和声学工程交叉领域的新兴领域。它探索了新型人造结构的设计和构造，例如声学超材料和声子晶体，以利用拓扑保护来稳健地操纵声波。拓扑声学的早期工作仅限于复制凝聚态物质系统中已理解的拓扑相，但最近的进展已转向探索在其他物理系统中难以实现的新拓扑概念，例如各种拓扑半金属相和拓扑相与 Floquet 工程、脆弱拓扑、非 Hermiticity 和合成维度相关。这些发展证明了拓扑声学系统的独特优势及其在发展拓扑物理学中的作用。在这篇综述中，我们调查了声学系统中拓扑相位的基本机制、基本设计和实际实现，并概述了未来的方向和潜在的应用。