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 …

Acoustic resonances in open systems, which are usually associated with resonant modes
characterized by complex eigenfrequencies, play a fundamental role in manipulating …

Mechanical metamaterials, also known as architected materials, are rationally designed
composites, aiming at elastic behaviors and effective mechanical properties beyond ('meta') …

Recently, higher-order topological insulators (HOTIs) as a novel frontier of topological
phases of matter have been induced in mechanical systems, opening new routes to …

Higher-order topological insulators (HOTIs) have attracted considerable attention because
of their topological properties of low-dimensional topological corner states and edge states …

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

The distinction and correlation between intrinsic and boundary-induced properties represent
a core problem in material physics. While resonant modes do not exist within band gaps in …

We report a new method to tailor the entire two-dimensional (2D) dispersion relation based
on nonlocal phononic crystals, where beyond-nearest-neighbor (BNN) interactions are used …

In elastic systems, the researchers have observed the topological valley edge states.
However, the topological valley edge states can only enable elastic waves to propagate …

Topology is the branch of mathematics studying the properties of an object that are
preserved under continuous deformations. Quite remarkably, the powerful theoretical tools …