Feeds

Cloaking device makes invisible progress

Light-emitting objects problem whacked

Top 5 reasons to deploy VMware with Tegile

Mathematicians have proposed improvements to cloaking technology to hide objects which emit their own electromagnetic radiation.

In October, a transatlantic team of scientists demonstrated the world's first working invisibility cloak, which uses metamaterials to bend electromagnetism around an object as if it weren't there.

However, the sums say the effect would be ruined by electromagnetic radiation from inside the cloak - so an object like a mobile phone, computer or aircraft could not be hidden. Analysis also showed that with current technology, to a person inside the cloak its inner surface would appear mirrored and they would not be able to see out.

A group led by Professor Allan Greenleaf at the University of Rochester, New York, said on Tuesday they had solved these problems with the invisibility cloak by revisiting the 19th century work of James Clerk Maxwell. Maxwell's four equations describe how electromagnetism interacts with matter.

The team propose two possible solutions to the twin issues; to line the inner surface with conductive materials tuned to the geometry of the cloak, or to "match" the outer metamaterial surface with an inner one. They say Maxwell's equations back up the fix.

With current metamaterials, devices are only able to provide a cloaking effect for a very limited wavelength range, as Greenleaf points out. He said: "For example, an object could be rendered invisible at just a specific wavelength of red; it would be visible in nearly every other color."

The new findings do seem to bring a functioning invisibility cloak nearer however. David R. Smith, a physicist at Duke University, part of the team which built the first cloak, said: "Allan has been looking at the problem much more generally, and deriving the conditions for when true invisibility is or is not possible. We are very interested in what he and his colleagues come up with!"

We're sure the news will also be read with great interest in the corridors of the DARPA, which funds Smith's work. ®

Beginner's guide to SSL certificates

More from The Register

next story
PORTAL TO ELSEWHERE scried in small galaxy far, far away
Supermassive black hole dominates titchy star formation
Boffins say they've got Lithium batteries the wrong way around
Surprises at the nano-scale mean our ideas about how they charge could be all wrong
Edge Research Lab to tackle chilly LOHAN's final test flight
Our US allies to probe potential Vulture 2 servo freeze
Europe prepares to INVADE comet: Rosetta landing site chosen
No word yet on whether backup site is labelled 'K'
Cracked it - Vulture 2 power podule fires servos for 4 HOURS
Pixhawk avionics juice issue sorted, onwards to Spaceport America
Archaeologists and robots on hunt for more Antikythera pieces
How much of the world's oldest computer can they find?
prev story

Whitepapers

Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.