Could the fantasy of invisibility become a reality?Silicone beads suspended in a water-based gel - © CRPP
Who hasn’t dreamed of wearing an invisibility cloak like Harry Potter? Thanks to metamaterials, this may soon become a reality. Researchers from the AMADEus Laboratory of Excellence recently developed the first acoustic metamaterials in 3 dimensions. Boasting electromagnetic properties unseen in any homogeneous natural material, metamaterials are composite materials capable of bending and controlling waves, in particular sound and light waves. Based on these uncommon properties, researchers have developed the first negative index 3D material supporting ultrasounds. To achieve this, they have created a new type of metamaterial, made up of porous silicone micro-beads suspended in a water-based gel, and literally had ultrasounds doing the moonwalk. These new-generation «flexible» metamaterials hint at numerous applications in ultrasound imaging (ultrasound scans, sound insulation, stealth in submarine acoustics, etc.) or for the manufacturing of materials. Most significantly, they bring the old fantasy of invisibility back into the limelight.
The results of this research were published in the Nature Materials journal on December 15, 2014.