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 …

Mechanical metamaterials exhibit some superior mechanical properties such as ultrahigh
strength-to-weight ratio, negative bulk-modulus, negative stiffness, negative mass-density …

Acoustic metamaterials can manipulate and control sound waves in ways that are not
possible in conventional materials. Metamaterials with zero, or even negative, refractive …

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

Acoustic metamaterials, structured to produce anomalous reflection and refraction indices
that are not found in conventional materials, are gaining prominence in engineering …

The advancement in electromagnetic metamaterials, which commenced three decades ago,
experienced a rapid transformation into acoustic and elastic systems in the forms of …

Complex fabrication process and expensive materials have restricted the development of
smart three-dimensional (3D) lightweight structures, which are expected to possess self …

We report a new class of tunable and switchable acoustic metamaterials comprising
resonating units dispersed into an elastic matrix. Each resonator consists of a metallic core …

Initially proposed to achieve strong noise isolation levels beyond the mass-density law,
acoustic metamaterials (AMMs) have now overturned the conventional views in all aspects …

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