Phononic crystals (PnCs) control the transport of sound and heat similar to the control of
electric currents by semiconductors and metals or light by photonic crystals. Basic and …

The introduction of engineered resonance phenomena on surfaces has opened a new
frontier in surface science and technology. Pillared phononic crystals, metamaterials, and …

Valley pseudospin, labeling the pair of energy extrema in momentum space, has been
attracting attention because of its potential as a new degree of freedom in manipulating …

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 …

The advances in topological condensed matter physics enable the manipulation of classic
waves in different ways, such as unidirectional propagation featuring the suppression of …

In elastic systems, the current technique to produce Dirac degeneracy is based on Bragg
scattering eigenstates, which, however, suffers from operating only at relatively high …

Dirac cones are essential features of the electronic band structure of materials like graphene
and topological insulators (TIs). Lately, this avenue has found a growing interest in classical …

Negative refraction of elastic waves has attracted significant research interest due to its
potential prospects in acoustic imaging, communication, and structural health monitoring …

Topological insulator (TI) that possesses topologically protected characteristic of guiding the
wave against disorders and structural perturbations without backscattering has attracted …

Valley interface states, resulting in acoustic valley Hall topological insulators, have recently
become a hot topic in the study of acoustic systems. On the basis of structural diversity and …