Topic description

The paradigm of topology has profoundly impacted condensed matter physics in recent years. This paradigm has been successfully extended to photonics and acoustics. A key outcome is the emergence of topologically protected edge, surface, and corner states, which exhibit remarkable robustness against defects and disorder.

This framework has been enabled by phononic crystals and acoustic metamaterials which are engineered structures offering unprecedented control over wave propagation. In acoustics, their macroscopic nature and experimental accessibility provide an ideal platform to explore novel wave phenomena while targeting concrete technological applications. Topological acoustic systems already enable robust waveguiding, delay lines, and offer strong potential for phononic circuits immune to fabrication imperfections. In elastodynamics, they support defect-immune guided modes relevant for optomechanics, on-chip acousto-optic modulation...