It’s rare when a scientific term is both cool sounding and precise, but the word “metamaterial” might just fit the bill. Although they are made from small, ordinary building blocks such as rods, circles or sticks, metamaterials have striking properties that often do not occur in the natural world.
Scientists have previously created metamaterials able to bend electromagnetic waves, such as microwaves, in opposite directions than ordinary materials would. Researchers have also been trying to use metamaterials to make so-called invisibility cloaks, in which certain colors of light would pass right around the metamaterial and make it harder to see.
Researchers can also create metamaterials with very unusual mechanical properties, as shown today at a meeting of the American Physical Society in San Antonio. For example, when you squeeze them with a constant force, they can crumple at different rates from moment to moment.
Katia Bertoldi of Harvard held a holey plastic metamaterial that looked like a pink Connect Four board, with a regularly repeating arrangement of holes. When squeezing the material, some holes became horizontal ovals, as you would expect in an ordinary material. But other holes, when squeezed, became vertical ovals, because of the way the metamaterial was designed. As Bertoldi squeezed the material further, some of the horizontal ovals transformed into vertical ones and vice versa. This allows metamaterials to have very different mechanical properties than ordinary materials. Read more…..