Discovery News reports that silk, a material used for thousands of years, could be the key to creating a soft, Harry Potter-style invisibility cloak:
For thousands of years people have worn shimmering silk to stand out in a crowd. Within the next few years people could wear silk to become invisible in a a crowd.
For the first time ever, scientists have created an invisibility cloak made from silk, and coated in gold.
The new metamaterial, as invisibility cloaks and their kin are technically called, only works on relatively long terahertz waves (a region of the electromagnetic spectrum between radio and infrared light), but the Boston-area scientists who developed the technology think that silk could work as an invisibility cloak at much smaller wavelengths, even in the visible range.
The research could lead to a wide range of optically unique materials for use in biomedicine or defense.
“This is an unusual angle for a metamaterial because of silk’s ability to interface with the human body,” something that no other metamaterial is currently capable of, said Fiorenzo Omenetto, a scientist at Tufts University who, along with colleagues at Boston University, helped develop the silk-based metamaterial and detail their new research in the journal Advanced Materials.
“On the sensing side it gives you a platform that is very adaptable.”
Invisibility cloaks, along with their optically exotic cousins, perfect absorbers and perfect reflectors and others, belong to a special class of materials known as metamaterials. Unlike most materials, which derive optical properties like color from their chemical make up, metamaterials derive their properties from the physical structure…
[continues at Discovery News]