Metamaterials (MMs), which include phononic crystals (PCs) as a particular type, exhibit
anomalous wave propagation properties through artificial design of topologies or lattice …

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 …

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 …

Metamaterials are man-made substances with unique spatial alternations in their constituent
components. They are widely used in modifying elastic, acoustic, or electromagnetic …

Guided waves, elastic waves propagating through bounded structures, play a pivotal role in
various applications, including ultrasonic non-destructive testing and structural health …

In this study, the periodic nested acoustic black hole phononic structure is presented, and
different complex band structures and corresponding evanescent Bloch wave propagation …

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

Local resonance band gaps in acoustic metamaterials are widely known for their strong
attenuation yet narrow frequency span. The latter limits the practical ability to implement …

Nonreciprocity can be passively achieved by harnessing material nonlinearities. In
particular, networks of nonlinear bistable elements with asymmetric energy landscapes have …

We investigate non-Hermitian elastic lattices characterized by non-local feedback
interactions. In one-dimensional lattices, proportional feedback produces non-reciprocity …