Topological acoustics is an emerging field that lies at the intersection of condensed matter
physics, mechanical structural design and acoustics engineering. It explores the design and …

Noise pollution has become a significant global problem in recent years. Unfortunately,
conventional acoustic materials cannot offer substantial improvements in noise reduction …

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 …

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 …

A quadrupole topological insulator, being one higher-order topological insulator with
nontrivial quadrupole quantization, has been intensely investigated very recently. However …

Effective manipulation of phonons is crucial to modern energy‐information science and
technologies but limited by the charge neutral and spinless nature of phonons. Recently …

The recent discovery of higher-order topological insulators (TIs) has opened new
possibilities in the search for novel topological materials and metamaterials. Second-order …

Chiral edge states that propagate oppositely at two parallel strip edges are a hallmark
feature of Chern insulators which were first proposed in the celebrated two-dimensional (2D) …

Topological phases of matter have attracted significant attention in recent years, due to the
unusual robustness of their response to defects and disorder. Various research efforts have …