13 August 2008

A METAMATERIAL THAT CREATES INVISIBILITY



Gustavo Quijano, a member of UAPSG/GEFAI has sent this valuable material for all those interested in Physics and in the very current issue of invisibility.

With the deserved thanks to Gustavo, here is the information:
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This information was developed by the Australian ABCnet.au

AM - Monday, 11 August , 2008  08:20:00

Reporter: David Mark


TONY EASTLEY: Invisibility it's traditionally the stuff of comic books and science fiction but scientists in California say they are one step closer to making invisibility a reality.

The scientists have invented a new three-dimensional "metamaterial" that can reverse the natural direction of light, creating the possibility of an invisibility cloak; just like Harry Potter's.

The researchers' work will be published later this week in two of the world's most prestigious scientific journals, Nature and Science.

David Mark reports.

DAVID MARK: Every now and then a scientific breakthrough comes along that truly captures the imagination.

And let's face it, who hasn't at one time or another dreamed that they could become invisible.

Now a team of scientists at the University of California, Berkeley has created a material that could one day make that happen. Harry Potter's invisibility cloak could become a reality.

JASON VALENTINE: If you were going to use this type of material for a cloak, yes it would bending around the material.

DAVID MARK: Jason Valentine a PhD student at Berkeley is one of the co-authors of the two papers that will be published later this week.

He's helped to create a new material that makes light bend in a way that isn't found in nature. It's similar to how light bends when it enters water and so a fish seen from an angle, will appear to be in a slightly different position to its actual position.

JASON VALENTINE: And do what we've been able to do is make a bulk material which bends light opposite to that of how it bends with naturally occurring materials. So for example in the fish in the water scenario; if the water was a medium with a negative index of refraction, the fish would actually appear to be above the water.

DAVID MARK: Scientists have previously created two-dimensional material that could bend light, but the team of Berkeley have gone one step further, they've created a three-dimensional material.

JASON VALENTINE: And so what we've done is taken this single layer and we've been able to stack the material, making a bulk material that's relatively thick. And also we've found that by making that material thicker, we actually can reduce the loss. So less light is absorbed in the material. And so this can really enable the vice applications; one of those applications could potentially be creating this cloaking.

DAVID MARK: Well let's go that one step further at least in our imagination: if you were to wear this material, what affect might it have on someone who was looking at you?

JASON VALENTINE: So if you were able to engineer the material properties in a certain manner and you wrapped someone in this material that's been designed, the person would essentially be invisible in that the light would bend around the person so you wouldn't see them at all.

DAVID MARK: For now the work is still in it's early days, Jason Valentine won't say when Harry Potter's invisibility cloak will move from the realm of science fiction or magic to reality.

JASON VALENTINE: We weren't really concentrating on any of the applications, we'll see where we it goes from here and what we pursue with it. But yeah it's a very fun area to be in for a scientist to be able to create a material that has properties that don't exist in nature is pretty cool from a scientist's standpoint.

TONY EASTLEY: We'll keep an eye on that one for you. The University of California, PhD Student, Jason Valentine, ending David Mark's report.

Related Audio:
    Full Interview with Jason Valentine on invisibility metamaterial
in:
RealMedia 28k+ WinMedia 28k+ MP3



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