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View Full Version : Move over Harry Potter, Duke develops invisibility cloak



OMEN
01-17-2009, 10:39 PM
University researchers use algorithms and new metamaterials to build cloaking device
Harry Potter has nothing on the researchers at Duke University, who say they're getting close to developing an actual invisibility cloak.

While the fictional wizard uses his cloak to roam the halls of Hogwarts and spy on his enemies, scientists at Duke say someday the cloak should be able to be used to improve wireless communications and shield seismic waves.

University researchers say their latest creation is more sophisticated than a more simple cloaking prototype they developed back in 2006. The new one, they noted, uses a new series of algorithms and composite materials called metamaterials. The magic, according to Duke, lies in the ability of the metamaterials to guide electromagnetic waves around an object and enable them to emerge on the other side as if they had passed through nothing but air.

"The difference between the original device and the latest model is like night and day," said David R. Smith, a researcher in Duke's Electrical and Computer Engineering department, in a written statement. "The new device can cloak a much wider spectrum of waves -- nearly limitless -- and will scale far more easily to infrared and visible light. The approach we used should help us expand and improve our abilities to cloak different types of waves."

According to Duke, the new materials in the cloaking device are able to bend electromagnetic waves. When the waves bend around the cloaking materials, it makes it appear as if the cloaked object isn't there at all.

The underlying cloaking phenomenon is similar to the shimmering mirages that seem to appear in the distance on hot days, Duke noted.

"You see what looks like water hovering over the road, but it is in reality a reflection from the sky," Smith said. "In that example, the mirage you see is cloaking the road below. In effect, we are creating an engineered mirage with this latest cloak design."

Duke's latest cloak, which measures 20 inches by four inches and is less than an inch thick, is made up of more than 10,000 individual pieces arranged in parallel rows, according to the university. Each piece is made of the same fiberglass material used in circuit boards and is etched with copper. And Duke also noted that the algorithms determine the shape and placement of each piece in the cloak.

The news from Duke wasn't the only announcement of a sci-fi-sounding development this week.

Earlier this week, a Massachusetts company that was founded four years ago by MIT graduates said that it's getting ready to take a flying car -- or, perhaps more accurately, a drivable aircraft -- on its first test flight. Richard Gersh, a vice president at the company, Woburn, Mass.-based Terrafugia Inc., told Computerworld that the company is preparing to take a prototype of the vehicle, dubbed The Transition to an airport in upstate New York for its initial flight.

The two-seater vehicle fits into the light sport aircraft category and has an anticipated price tag of $148,000. Gersh said that the company so far has received more than 40 orders for The Transition. He hopes the first one will be in a customer's hands by next year.

Compworld

JohnCenaFan28
01-18-2009, 10:47 PM
Thanks for posting.