Mechanical vibrations are being harnessed for a variety of purposes and at many length scales, from the macroscopic world down to the nanoscale. The considerable design freedom in mechanical structures allows one to engineer new functionalities. In recent years, this has been exploited to generate setups that offer topologically protected transport of vibrational waves (topological phonon transport), both in the solid state and in fluids. Borrowing concepts from electronic physics and being cross fertilized by concurrent studies for cold atoms and electromagnetic waves, this field of topological transport in engineered mechanical systems offers a rich variety of phenomena and platforms. In this Colloquium, a unifying overview of the various ideas employed in this area is provided, different approaches and experimental implementations are summarized, and the challenges as well as the prospects are commented upon.

中文翻译：

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研讨会：工程机械系统中的拓扑保护传输

机械振动被用于多种目的和多种长度尺度，从宏观世界到纳米尺度。机械结构的相当大的设计自由度允许人们设计新的功能。近年来，它已被用来生成提供拓扑保护的振动波传输（拓扑声子传输）的装置，无论是在固态还是在流体中。工程机械系统中的拓扑输运领域借鉴了电子物理学的概念，并通过对冷原子和电磁波的并行研究进行了交叉融合，提供了丰富多样的现象和平台。在本次研讨会上，对该领域所采用的各种想法进行了统一概述，总结了不同的方法和实验实施，并对挑战和前景进行了评论。