tagged w/ Metamaterials
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Stealth Metamaterials A B-2 Spirit bomber flying over Guam. A team of researchers from Purdue University and Norfolk State University in Virginia designed a new metamaterial that absorbs almost all the light that hits it, heralding a new wave of stealth technology. Wikimedia commons/US Air Force
A new blacker-than-black metamaterial absorbs almost all the light that hits it, heralding a new breed of stealth technology.
The material's internal structure absorbs almost all the electromagnetic radiation in a particular range, New Scientist reports. Ordinary black objects, by contrast, always reflect a bit of light. The material could be applied to all parts of the electromagnetic spectrum, meaning it could be used to make materials invisible to radar.
Rebecca Boyle, black, color, metamaterials, nanowires, radiation, stealth, stealth technology, visionDesigned by Evgenii Narimanov of Purdue University, Mikhail Noginov of Norfolk State University in Virginia and their colleagues, the material consists of silver nanowires embedded in very thin 0.4-inch aluminum oxide squares. Their array-like structure gives them their unusual properties, New Scientist says.
Man-made metamaterials can also bend light to create invisibility cloaks, ultra-thin sound-proof walls and even miniature Big Bangs and megaverses.
The researchers tested their new black material with near-infrared radiation, just beyond the red end of the visible spectrum. When the radiation hit the polished material at less than 45 degrees from perpendicular, about 20 percent of the radiation bounced off. When they roughened the material so it wasn't smooth, less than 1 percent of the radiation bounced off.
Narimanov told New Scientist the technology would likely be used to build radar-proof stealth equipment.Stealth Metamaterials A B-2 Spirit bomber flying over Guam. A team of researchers from... more
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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.The goal at hand, changing how objects interact with light, seemed at first blush to... more
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It's like something out of a science fiction novel or a Harry Potter book. Engineers from Duke University have constructed a device that can "cloak" items placed on a mirror surface.
First designed in 2006, the new version of the device is a more sophisticated and complicated design that can cloak a wider variety of waves. To create the new device, the researchers developed a new set of mathematical algorithms which, in turn, are used to engineer artificially structured "metamaterials" that have properties not found in natural materials. The metamaterials are what form the cloaking structures, which bend electromagnetic waves, like light, around an object, so it appears the object is no longer there.
[More at Link]It's like something out of a science fiction novel or a Harry Potter book.... more
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According to the National Nanotechnology Initiative, "The worldwide need for nanotechnology workers is expected to reach 2 million by 2015."According to the National Nanotechnology Initiative, "The worldwide need for... more
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These are graphical representations of numerical simulations depicting four potential applications of a new field called transformation optics. Clockwise from top left are: a design for optical cloaking; a light "concentrator" for sensors and solar collectors; a "planar hyperlens" and "impedence-matched hyperlens" for applications including microscopes. (Courtesy of the journal Science)
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A new research field called transformation optics may usher in a host of radical advances including a cloak of invisibility and ultra-powerful microscopes and computers by harnessing nanotechnology and "metamaterials."
These are graphical representations of numerical simulations depicting four potential... more
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Japanese scientist Professor Susumu Tachi claims to have developed this 'invisibility coat' which creates an optical illusion of invisibility. Scientists at the University of California are also making investigations into the manipulation of light, and specifically the ability to render objects invisible.Japanese scientist Professor Susumu Tachi claims to have developed this... more
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A huge increase in the speed of the internet could be produced by slowing parts of it down, say researchers.
Applying the brakes could be the "metamaterials" that may make it possible to create invisibility cloaks. The net's speed limit comes about not in transporting information, but in routing it to its various destinations. Metamaterials could replace the bulky and slow electronics that do the routing, paving the way for lightning fast speeds.
High-speed telecommunications routes include fibre-optic cables that span vast distances, carrying different streams of information in different channels—each with its own frequency of light. As data nears the end of its journey, these frequencies must be separated and sent to their destinations. The separation is accomplished with bulky equipment that spreads the closely spaced frequencies in the pulses into different detectors.
The light must then be converted into electrical signals which are stored, routed, and turned back into optical signals with lasers. The conversion, besides adding significant cost and complexity, also slows down the data transmission.
(continued at link)A huge increase in the speed of the internet could be produced by slowing parts of it... more
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WASHINGTON (AP) -- Scientists say they are a step closer to developing materials that could render people and objects invisible. Researchers have demonstrated for the first time they were able to cloak three-dimensional objects using artificially engineered materials that redirect light around the objects.
Previously, they only have been able to cloak very thin two-dimensional objects.
The findings, by scientists at the University of California, Berkeley, led by Xiang Zhang, are to be released later this week in the journals Nature and Science.
The new work moves scientists a step closer to hiding people and objects from visible light, which could have broad applications, including military ones.
People can see objects because they scatter the light that strikes them, reflecting some of it back to the eye. Cloaking uses materials, known as metamaterials, to deflect radar, light or other waves around an object, like water flowing around a smooth rock in a stream.
Metamaterials are mixtures of metal and circuit board materials such as ceramic, Teflon or fiber composite. They are designed to bend visible light in a way that ordinary materials don't. Scientists are trying to use them to bend light around objects so they don't create reflections or shadows.
It differs from stealth technology, which does not make an aircraft invisible but reduces the cross-section available to radar, making it hard to track.
The research was funded in part by the U.S. Army Research Office and the National Science Foundation's Nano-Scale Science and Engineering Center. WASHINGTON (AP) -- Scientists say they are a step closer to developing materials that... more
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Scientists recently achieved an important milestone in the field of stealth research.
By creating exotic "metamaterials" which have unique nano-scale structures, new mystical effects are being observed and exploited.
Not too long ago, a structure capable of deflecting radar in a puzzling way was demonstrated. Now, scientists have upped the ante by reducing the size of those structures, and along with it, the wavelength of the energy waves with which it interacts.
This recent advance suggests that the researchers are on the right track, and may soon further improve the technology to work in the realm of visible light.
The effects can best be described as light flowing around the cloaked object much like water flows around a rock in a stream.
The military is especially interested in the implications of these discoveries.
"Peeping-toms" everywhere rejoice.Scientists recently achieved an important milestone in the field of stealth research.... more
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