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 …

Phononic crystals (PCs) and metamaterials (MMs) can exhibit abnormal properties, even far
beyond those found in nature, through artificial design of the topology or ordered structure of …

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

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 …

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') …

Abstract Space− time modulated metamaterials support extraordinary rich applications, such
as parametric amplification, frequency conversion, and non-reciprocal transmission. The …

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 …

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 …

In superconducting quantum circuits (SQCs), chiral routing quantum information is often
realized with the ferrite circulators, which are usually bulky, lossy and require strong …