The law of reciprocity in acoustics and elastodynamics codifies a relation of symmetry
between action and reaction in fluids and solids. In its simplest form, it states that the …

The topological properties of an object, associated with an integer called the topological
invariant, are global features that cannot change continuously but only through abrupt …

The concept of topological energy bands and their manifestations have been demonstrated
in condensed matter systems as a fantastic paradigm toward unprecedented physical …

In solid state physics, a bandgap (BG) refers to a range of energies where no electronic
states can exist. This concept was extended to classical waves, spawning the entire fields of …

Topological mechanical metamaterials have emerged with the development of topological
phases and topological phase transitions in modern condensed matter physics. Their …

Energy in lower dimensions, such as edges or corners, can be robustly confined by the
higher-order topological insulators (HOTIs) against defects. Being promising for wave …

Topological insulators have attracted intensive attention due to their robust properties of
path defect immunity, with diverse applications in electromagnetic, acoustic, and elastic …

Broadband attenuation of low frequency acoustic waves in compact structure designs is a
challenging issue, especially in the application to seismic waves. In this work, we propose a …

Topological elastic metamaterials have emerged as a new frontier in the quest of topological
phases in condensed matter physics. Their exotic topological properties open a wealth of …

We experimentally achieve wave-mode conversion and rainbow trapping in an elastic
waveguide loaded with an array of resonators. Rainbow trapping is a phenomenon that …