Knowledge Center
Knowledge Center


Artificial materials containing arrays of metal nanostructures or mega-atoms.


Metamaterials are artificial materials containing arrays of metal nanostructures or mega-atoms. These materials are a “synthetic composite with a structure such that it exhibits properties not usually found in natural materials, especially a negative refractive index.”1

Some metamaterials are able to bend light around objects, rendering them invisible. But they only interact with light over a very narrow range of wavelengths, according to researchers. Some silicon-based metamaterials are enabling photonic circuits —computer circuits that use photons instead of bits. Acoustic metamaterials, which are normal materials, such as plastic, paper, wood or rubber, but engineered so that their internal geometry sculpts the sound going through. Researchers are exploring ways to make acoustic lenses using metamaterials. “The idea of acoustic lenses has been around since the 1960s and acoustic holograms are starting to appear for ultrasound applications, but this is the first time that sound systems with lenses of practical sizes, similar to those used for light, have been explored,” said Gianluca Memoli from the University of Sussex.

Purdue Researchers have taken a step toward practical applications for hyperbolic metamaterials, which are ultra-thin crystalline films that could bring optical advances for microscopes, quantum computers and high-performance solar cells. Optical metamaterials harness clouds of electrons called surface plasmons to manipulate and control light. However, some of the plasmonic components under development rely on the use of metals such as gold and silver, which are incompatible with the complementary metal–oxide–semiconductor (CMOS) manufacturing process used to construct integrated circuits and do not transmit light efficiently, the researchers said.

Metamaterial types fall into these categories:

  • Acoustic metamaterials
  • Optical metamaterials
  • Plasmonic metamaterials
  • Thermal metamaterials
  • Transparent metamaterials
  • Magnetic metamaterials
  • Hyperbolic metamaterials
  1. Source: Google dictionary definition.