Bending Energy Waves

“Elastic” waves are energy waves that pass through or over the surface of a material without permanently changing it. They include waves like sound passing through air or shockwaves moving through water. The ability to manipulate these types of energy has the potential to create super high-resolution sensors, enhance hearing devices, advance imaging technologies through the development of super-lenses and a host of other commercial, military and medical applications.

Past attempts at controlling elastic waves have been only marginally successful. But scientists recently designed and engineered a structural material that brings them one step closer. Using a single sheet of steel, they engraved a geometric microstructure pattern. The pattern possesses a quality called “chirality,” a property of asymmetry which means that it cannot be superimposed on its mirror image, similar to the difference between a person’s right and left hand. This allows them to “bend” elastic waves and focus them more directly. Integrating active components will further enable the researchers to “tune in” to any elastic wave frequency and ultimately control how it reacts to its surroundings.