Diffusion driven by temperature or concentration gradients is a fundamental mechanism of
energy and mass transport that inherently differs from wave propagation in both physical …

Diffusion and wave propagation are both fundamental transport mechanisms, but they have
intrinsically different dynamics, governing equations, and applications. Over the past …

Despite the emergence of acoustic metamaterials with superior sound absorption and
transmission loss, their adoption for building sound insulation has been limited. Sound …

Inspired by the gradient structures of biological materials, researchers have explored
compositional and structural gradients for about 40 years as an approach to enhance the …

Metamaterials are composed of periodic subwavelength metallic/dielectric structures that
resonantly couple to the electric and magnetic fields of the incident electromagnetic waves …

Acoustic metasurfaces derive their characteristics from the interaction between acoustic
waves and specifically designed materials. The field is driven by the desire to control …

Because of analogies between the 2D Maxwell equations and water wave equations,
methods for manipulating electromagnetic waves based on photonic crystals and …

Frequency conversion processes, such as second-and third-harmonic generation, are
commonly realized in nonlinear optics, offering opportunities for applications in photonics …

Tunable metamaterials without the necessity to redesign parameters and remanufacture
have received increasing interest in recent years due to their rich dynamic characteristics …

Free from phase-matching constraints, plasmonic metasurfaces have contributed
significantly to the control of optical nonlinearity and enhancement of nonlinear generation …