Acoustic, electromagnetic and seismic metamaterials - For nano- to metric-scale waves

Since the discovery of photonic crystals in 1987, wave physicists have been developing theoretical and numerical models for the enhanced control of light in nanoscale structured materials, and of sound on the micrometer scale, and have been inspired by them to go so far as to seek the control of elastic Rayleigh waves in metric-scale structured soils. A new kind of "mineral", yablonovite, artificially formed from a network of hollow cylinders a few tens of nanometers in diameter in a glass block, has inspired the structuring of matter at different scales. The paradigm shift continues towards electromagnetic metamaterials for photonics, and seismic metamaterials for civil engineering, with structured soils and metasurfaces with resonators on the earth's surface. Interaction between disciplines is accelerating, with mutually beneficial developments. For example, the emergence of locally resonant elastic metamaterials shows promising potential in vibro-acoustics. However, the transition to engineered solutions still requires robust performance predictions. Taking damping into account in the mechanical systems studied leads to peak attenuation, but also brings the desired vibro-acoustic performance at wider bandwidths. This article takes stock of the revolution underway in extending the principles of wave interaction with matter to everyday technologies.