Material Could Repel Laser Attacks

Feb. 26, 2008 -- Researchers at the U.S. Navy's China Lake Naval Warfare Center are developing a new material that would shield ships against high-energy weapons like lasers.

The work could help protect equipment and personnel while advancing research in the unique world of metamaterials.

"If you have a ship being hit by a laser, and it was made of this metamaterial, you could reflect the laser beam," said Simin Feng, one of the study co-authors and a researcher at China Lake.

Unlike normal materials, which derive their properties largely from the chemicals that comprise them, metamaterials are artificially made materials that get their properties from their physical structures.

The material Feng and her co-author Klaus Halterman, also of China Lake, have theorized would be made of three layers of conventional materials, with the metamaterials sandwiched between the three layers. Since the material would be thin it should be easily applied and "wouldn't weigh things down," said Halterman.

There are several kinds of metamaterials. Some, like the "invisibility cloak" developed by Duke University Researchers in 2006, channel certain wavelengths of light around a hidden object. Others, like the Navy's, have what is called a negative refractive index.

Stick a straw into a glass of water. The parts above and below the water point in slightly different directions. That's a positive refractive index, and is the case for nearly all materials.