Feeds

'Perfect' INVISIBLE SHED stuns boffinry world

Not a cloak. Not strictly invisible either, at that

The smart choice: opportunity from uncertainty

Invisibility cloaks - or, more correctly, sheds - inched a little closer to reality this week with the revelation that scientists have made an object flawlessly invisible.

Previous attempts to make objects invisible had succeeded in bending light around their edges, but left a dark shadow behind the object because of some light reflecting off it. This time, there was no reflection, no shadow and the object was perfectly invisible.

Unfortunately the object was a static 1cm tall cylinder, it was only invisible to microwaves (not visible light) and the invisibility effect only worked from one angle. Boffins have not yet succeeded in making invisibility cloaks for large moving objects in visible light. As and when they do, we have on the authority of top invisibility boffin John Pendry that the result will not be anything cloak-like.

"This isn't anything that flaps around in the breeze; it's more like a shed," he commented in 2006.

Measured electric field data for free space, the cloak and a copper cylinder at the optimum cloaking frequency of 10.2 GHz, credit, paper authors Nathan Landy & David R. Smith Nature Journal

Cloaking a copper cylinder from microwaves with a diamond shaped shield, Nathan Landy, published Nature Journal

However the boffins' work now published marks a big advance in the field of transformation optics and is a milestone in a huge area of research that could transform computers.

According to the BBC, the trick was to use a diamond-shaped cloak, with properties carefully matched at the diamond's corners, to shuttle light perfectly around a cylinder 7.5cm in diameter and 1cm tall.

It only worked from one direction.

"It's like the card people in Alice in Wonderland," lead researcher Professor David Smith from Duke University, told the BBC. "If they turn on their sides you can't see them but they're obviously visible if you look from the other direction."

Scientists told the BBC it would be very hard to implement the same effect with visible light.

Either the object has to be really tiny or else the type of radiation being used has to be long - with say microwaves 1mm-1m, or radio waves 1mm to 100km. Optical lightwaves are just a few hundred billionths of a metre.

While invisibility cloaks seem far off, the uses in other fields are manifold: from heat-cloaking processors in computers, to using optics as an alternative to electronics in computers to multiple military and telecoms uses including cloaking ships from detection and ramping up the speed of the internet.

As Professor Smith and grad researcher David Landy write in their abstract:

In 2006, invisibility became a practical matter for the scientific community as well, with the suggestion that artificially structured metamaterials could enable a new electromagnetic design paradigm, now termed transformation optics.

®

Research paper 'A full-parameter unidirectional metamaterial cloak for microwaves'by Nathan Landy and David R Smith was published in Nature on 11th November 2012

The Power of One Infographic

More from The Register

next story
World Solar Challenge contender claims new speed record
One charge sees Sunswift travel 500kms at over 100 km/h
SMELL YOU LATER, LOSERS – Dumbo tells rats, dogs... humans
Junk in the trunk? That's what people have
The Sun took a day off last week and made NO sunspots
Someone needs to get that lazy star cooking again before things get cold around here
Boffins discuss AI space program at hush-hush IARPA confab
IBM, MIT, plenty of others invited to fill Uncle Sam's spy toolchest, but where's Google?
Bad back? Show some spine and stop popping paracetamol
Study finds common pain-killer doesn't reduce pain or shorten recovery
Forty-five years ago: FOOTPRINTS FOUND ON MOON
NASA won't be back any time soon, sadly
Jurassic squawk: Dinos were Earth's early FEATHERED friends
Boffins research: Ancient dinos may all have had 'potential' fluff
prev story

Whitepapers

Top three mobile application threats
Prevent sensitive data leakage over insecure channels or stolen mobile devices.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Boost IT visibility and business value
How building a great service catalog relieves pressure points and demonstrates the value of IT service management.
Designing a Defense for Mobile Applications
Learn about the various considerations for defending mobile applications - from the application architecture itself to the myriad testing technologies.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.