Metamaterial Revolution: The New Science of Making Anything Disappear

[Orsino]

From this month's Discover magazine:

Xiang Zhang remembers the day he recognized that something extraordinary was happening around him. It was in 2000, at a workshop organized by DARPA (the Defense Advanced Research Projects Agency) to explore a tantalizing idea: that radical new kinds of engineered materials might enable us to extend our control over matter in seemingly magical ways.

The goal at hand, changing how objects interact with light, seemed at first blush to be routine; people had been manipulating visible light with mirrors and lenses and prisms nearly forever. But Zhang, a materials scientist then at the University of California at Los Angeles, knew those applications were limited. Based overwhelmingly on a single material, glass, the technologies were restricted by the laws of optics described in standard physics texts. The engineers in the room hoped to smash through those barriers with materials and technologies never conceived of before. The proposals included crafting what amounts to an array of billions of tiny relays; in essence, the relays would capture light and send it back out. Depending on the specific design of the array, the light would be bent, reflected, or skewed in different ways.

What could you do with a tool like that? An amazing amount, Zhang soon discovered. For one thing, you could render objects invisible. You see something, after all, when light bounces off it, creating the reflections that enter your eye and form an image on your retina. If you could direct light to flow smoothly around the object like water flowing past a rock in a stream, there would be no reflection, no rays entering your eye, and nothing to see—not even a shadow.

[BeFree]

1. Better yet

Tiny tvs mounted facing the viewer showing pics taken from the other side.

Think of it as if your tv showed a picture of the wall behind it.

Gone!

[MineralMan]

2. I've seen several reports on this but haven't seen

any photos of it in action. Has anyone?

[cliffordu]

3. Nope. They turned the fucking thing on and it disappeared.

[Orsino]

4. The article is tantalizing, but...

...my first thought was also, "Where is this disk that is better than an electron microscope? What does it look like?" Not enough pictures. Anyone can whomp together an image of a ball surounded by diverging and converging lines. I want to see this tech.

[Salviati]

5. Because they've only gotten it to work with reletively long wavelengths...

Well outside the visible spectrum.

The main problems are twofold:

Building such a meta material means engineering on a scale comparable to the wavelength you want the device to work at. So building something to work at long wavelengths is much easier than making something to work in the visible spectrum, where you're talking about building a matrix of material with structures on the order of 1/2,000,000 th of a meter.

the other problem is the bandwidth over which the device will act. The simplest meta materials will work well for 1 wavelength, and will get increasingly worse as the wavelength of light differs from that ideal frequency. Ideally we'd want a material to work well over a broad spectrum of wavelengths which would complicate the design.