cloaking device built

Scientists have made the impossible possible, disappearing a cylinder by guiding light around it before putting those photons back on their original path -- essentially bending light around the object. This new approach achieves invisibility where others have failed. With a catch, however: It only works from one direction.

The math is incredibly complex and the materials necessary difficult to produce. And while the underpinning concepts allow invisibility in microwaves and hold promise for radar, it won't be easy to make it work at optical wavelengths, cautioned Duke University’s Nathan Landry and John Pendry of London’s Imperial College, who published their results in the journal Nature Materials.

Still, it's a breakthrough six years in the making. The team made their initial discovery in 2006, a new approach to “transportation optics”: artificially structured stuff called meta-materials designed with specific properties. In this case, they move light around in particular ways to shape an electromagnetic signature, hiding an object from radar and some types of cameras.

“We built the cloak, and it worked,” said Landy, a graduate student working in the laboratory at Duke’s Pratt School of Engineering. “It split light into two waves which traveled around an object in the center and re-emerged as the single wave minimal loss due to reflections.”

There are drawbacks to even this research effort, of course. It can only hide objects so small they are not visible to the naked eye, and that success has predominantly been in wavelengths longer than what the eye can, see such as infrared, microwaves and radio.