Communications Physics (Jan 2022)
Robust separation of topological in-plane and out-of-plane waves in a phononic crystal
Abstract
Judicious design of acoustic metamaterials has so far permitted control of topologically-protected waves in one plane of a two-dimensional system. Here, the symmetry of a phononic crystal is tuned geometrically to realise independent tuning of both in-plane and out-of-plane topological modes in the same frequency range.