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

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

In this study, we design the 3D-printed phononic crystal (PnC) beam with the topological
interface state for harvesting the mechanical energy of flexural waves. The PnC beam is …

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 …

In this work, we experimentally achieve 1-kHz-wide directional band gaps for elastic waves
spanning a frequency range from approximately 8 to 11 kHz. One-way propagation is …

We experimentally demonstrate temporal pumping of elastic waves in an electromechanical
waveguide. Temporal pumping exploits a virtual dimension mapped to time, enabling the …

Research on breaking time-reversal symmetry to realize one-way wave propagation is a
growing area in photonic and phononic crystals and metamaterials. In this Letter, we present …

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

Topological phononic crystals have attracted intensive attention due to their peculiar
topologically protected interface or edge states. Their operating frequency, however, is …