metamaterial
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'Metamaterial' can switch from soft to hard - and back again
University of Michigan researchers have developed a technique for a new 'metamaterial' that can change its level of solidness, but without damaging or changing the material itself. Metamaterials are man-made materials whose properties come from the way it's constructed rather than what it's composed from. Scientist can then tinker with its structure to affect its properties. Those effects can be very broad: researchers were able to create a camera that doesn't require a lens to work using different man-made materials. This one's different again.
Scientists make a Mobius strip of laser light
Unless you count incidents in Star Trek episodes, Möbius strips don't really occur in nature -- you have to create that freaky one-sided shape yourself. However, a worldwide team of scientists may have produced the next best thing. They've created a Möbius strip of light by manipulating the polarization of the light's inherent electromagnetic field. The trick involves firing a highly focused laser beam through a liquid crystal lens to give it a very specific polarization. When the light scatters at the focal point with the help of a nanoparticle, that polarization creates tiny, twisted loops. While these strips were made in a lab, of course, the experiment shows that they're at least possible in nature.
Invisibility suits are coming thanks to squid-like displays
It's not as hard to make an invisibility cloak as you might think, but making one that's truly sophisticated is another matter; metamaterials (substances that change the behavior of light) are hard to build. Rice University appears to have solved part of the problem, however. It just developed a squid-like color display (shown below) that should eventually lead to smart camouflage. The new technology uses grids of nanoscopic aluminum rods to both create vivid, finely-tuned colors as well as polarize light. By its lonesome, the invention could lead to very sharp, long-lasting screens. The pixels are about 40 times smaller than those in LCDs, and they won't fade after sustained light exposure.
Metamaterial camera needs no lens, could herald cheaper imaging tech
Metamaterials are proving to be quite useful for toying with the electromagnetic spectrum, whether for technology previously thought to be the stuff of science fiction, or for boring real-world applications. Engineers at Duke University have come up something that falls more into the latter category: a metamaterial imaging sensor that doesn't require a lens to generate a picture. The sensor is a flexible copper-plated sheet patterned with small squares that capture various light frequencies all at once, functioning like one big aperture. Add a few circuits with a pinch of software and the sensor-only camera can produce up to ten images per second, but the catch is Duke's only works at microwave frequencies. Microwave imaging is used plenty, however, and due to its flexibility and lack of moving parts, the sensor could be used to build better integrated, cheaper airport scanners and vehicle collision avoidance technology -- making you safer however you choose to travel. Unless you take the train. Then you're on your own.
Intellectual Ventures launches Kymeta spinoff, promises slim satellite broadband hotspots
Intellectual Ventures is best known for its tendency to sue everyone, but it's going some distance to mend that bruised image through a newly spun out company, Kymeta. The startup hopes to improve the quality of satellite broadband through mTenna-branded, Ka-band hotspots made from metamaterials -- substances that can boost and manipulate a satellite signal while occupying virtually no space, leading to self-pointing transceivers that are just a fraction of the size of what we use today. That still amounts to equipment the size of a laptop running at a peak 5Mbps, although it's small enough that Kymeta sees hotspots reaching individual customers who want access from a boat, a car or the field. We'd just advise against tossing out the MiFi too quickly. Kymeta doesn't expect the hotspot to be ready before late 2014 at the earliest, and that leaves many questions about how much of a hit we'll take to the pocketbook.
UT Dallas researchers seek to imbue your smartphone with X-ray superpowers
If anybody ever told you that the future would be awesome, they were right. A new bit of research has emerged from the University of Texas at Dallas, which describes equipment that may allow people to see through walls -- and if that weren't wild enough, creators of the specialized CMOS imaging hardware believe the same technology could be integrated into our mobile phones. To pull off the feat, the scientists tapped into a portion of the electromagnetic spectrum that exists between microwave and infrared known as the terahertz range. Due to privacy concerns, the equipment is being designed to operate at a distance of no more than four inches, but its creator hypothesizes that the technology will still be useful for finding studs in walls, verifying documents and detecting counterfeit currency. In other words, this brand of x-ray vision isn't exactly on par with Superman's abilities, but it's bound to work better than mail order spectacles from Newark.
The Amazing Gecko-Man: a superhero future made possible by probable science
There's no superhero origin story that begins with a bite (or a lick?) from a gecko. Plain 'ol wall climbing powers are, it seems, just not as sexy as wearing skintight suits, slinging webs and crawling up buildings. But if a few bright minds at the University of Southampton have anything to say about it, we could soon find ourselves walking like real-life lizard people (V, anyone?) and suctioning onto various surfaces using the managed properties of light. Lead researcher John Zhang and his UK team have predicted the existence of a force more powerful than gravity and the short-range pull of the Casimir effect, whereby plasmons (electromagnetic waves) captured on a metamaterial and the electrons on a metal resonate and form a bond of attraction. The resultant particle field is supposedly strong enough to "overcome the Earth's gravitational pull" and could even be used to alter the reflectivity of a material. Obvious military and aerospace applications aside, this invisible adhesive could also make its way into our everyday lives -- they just need to need to prove that it, y'know, actually exists first.
Metamaterial printing method inches us closer to invisibility cloaks
In theory, metamaterials are all kinds of awesome -- they can boost antenna strength, focus lasers, and create invisibility cloaks. But, they've been limited to day dreams lab experiments because producing the light-interfering materials in any practical quantity has been difficult and time consuming. John Rogers, a professor at the University of Illinois has figured out a way to print a layered, nano-scale mesh that bends near-infrared light in much larger amounts than previously possible. The new method, based around a plastic stamp, has been used to create sheets of metamaterial measuring a few square inches, but Rogers is confident he can scale it up to several feet. Who knows, by the time the second installment of The Deathly Hallows hits theaters in July you could get the best Harry Potter costume -- one that lets you sneak in without shelling out $13. [Thanks, Plum G.]
Scientists put color on your bling with micro carvings, gangsters pacified
Remember that time when you sipped some herbal tea and thought, "I really want a pink gold ring?" Yeah, that was some good tea alright, but the brainiacs at the University of Southampton have actually found a way to achieve this potential fashion trendsetter. The idea is simple: rather than coating metals -- especially naturally colored ones like gold and copper -- with paint, these folks alter their color by using an ion beam to carve fine patterns that are smaller than visible light's wavelength. The resultant metamaterial dramatically boosts the metals' light absorption efficiency, thus reflecting a different color depending on the pattern's radius and etch depth. So for instance, gold can reflect colors ranging from orange to red to green to brown with its ring pattern etch depth ranging from 85nm to 205nm, respectively. See? We told you it's simple, but there's also some visual aid after the break to wrap up this science lesson.
Flexible metamaterial could make your next invisibility cloak rather more comfortable
Metamaterials have a lot of potential future applications, but only one of them really gets our geeky senses tingling: invisibility cloaks. Previous theoretical examples we've seen were built upon rigid silicon substrates, meaning they'd be about as comfortable to wear as a motherboard jacket with ISA sleeves. But, a new material at the University of St. Andrews has been created that offers similar light-bending properties in a flexible package, crafted by the formation of a membrane upon a release layer, etching microscopic gold bars upon it, and then removing the release layer to have just the blingy membrane left behind. It can be tuned to bend various wavelengths, with the team having success working at wavelengths as short as 620nm -- you know, red. If there's one problem it's the size of the thing, with current prototypes measuring just 5 x 8mm, but it is said to be "scalable to industrial levels," meaning next-year's Harry Potter costume could be the best one ever.
Metamaterials used to focus Terahertz lasers, make them useful
Forget old and busted X-rays, T-rays are the future, man! It was only recently that we were discussing Terahertz lasers and their potential to see through paper, clothes, plastic, flesh, and other materials, but that discourse had to end on the sad note that nobody had managed to make them usable in a practical and economically feasible way. The major hurdle to overcome was the diffusion of Terahertz radiation -- which results in weak, unfocused lasers -- but now researchers from the universities of Harvard and Leeds seem to believe they've managed to do it. Using metamaterials to collimate T-rays into a "tightly bound, high powered beam" will, they claim, permit semiconductor lasers (i.e. the affordable kind) to perform the duties currently set aside for sophisticated machinery costing upwards of $160,000. Harvard has already filed a patent application for this innovation, and if things pan out, we might be seeing body scanners (both for medical and security purposes), manufacturing quality checks, and a bunch of other things using the extra special THz stuff to do their work.
Terahertz radiation and metamaterials combine to form super X-Ray specs
It looks like somebody actually coughed up the extra dollar for the De Luxe model X-Ray specs in the back of Mad Magazine, then reverse-engineered 'em in the name of science. That somebody is Richard Averitt, whose team at Boston University has come up with a way to use metamaterials and terahertz transmissions to see through you. We've seen metamaterials plenty of times before, typically being used for nefarious deeds on the opposite end of the spectrum: invisibility cloaks. Here they form pixels for a digital imager that can be activated by THz radiation. If you're not familiar with THz radiation, it's a (supposedly perfectly safe) form of energy waves that pass through materials -- much like X-Rays but without all the nasty DNA-shattering effects on the way through. There's just one problem: nobody (not even this guy) has made a powerful enough THz emitter just yet, meaning we're all safely naked under our clothes for at least another few years.
3D invisibility cloak fashioned out of metamaterials
Those HDTV manufacturers did tell us that 3D was going to be everywhere this year, didn't they? Keeping up with the times, scientists investigating potential methods for rendering physical objects invisible to the human eye have now moved to the full three-dimensional realm. The Karlsruhe Institute of Technology has developed a photonic metamaterial that can make things disappear when viewed from all angles, advancing from previous light refraction methods that only worked in 2D. It sounds similar to what Berkeley researchers developed not too long ago, and just like Berkeley's findings, this is a method that's still at a very early stage of development and can only cover one micrometer-tall bumps. Theoretically unlimited, the so-called carpet cloak could eventually be expanded to "hide a house," but then who's to say we'll even be living in houses by that time?
First electromagnetic 'black hole' built on earth, nobody raps about it
An electromagnetic black hole -- which sucks in the light surrounding it -- has been built at Southeast University in Nanjing, China for the first time. The device works like cosmological black holes in that it has gravity which is intense enough to bend the surrounding space-time, causing any matter in the neighborhood to spiral inward and create the hole itself. The earth-built 'black hole' for microwave frequencies is constructed of 60 annular strips of meta-materials (yes, that's the stuff of invisibility cloaks). Each strip is an intricately etched circuit board which seamlessly and smoothly connects to the strips next to it, creating both a shell and absorber section to the device. When an electromagnetic wave hits the device, it is trapped and guided through the shell region toward the core, where it is absorbed. The device, which was created by Tie Jun Cui and Qiang Cheng, converts that absorbed light into heat, meaning that future possible applications could include new ways of harvesting solar energy. Hit the read link for a fuller description of this truly bad dude.
Universal mirrors: more useful, less fun than carnival mirrors
You know those invisibility cloaks scientists have been struggling to master for decades? This here is said cloak's perfect opposite, and it's bending our minds in ways you can hardly fathom. Ulf Leonhardt, a professor at the University of St. Andrews, has worked with a brilliant team of scientists in order to construct what he calls a universal mirror, or if we're being proper, an omnidirectional retroreflector. Unlike conventional mirrors which simply reflect objects at 90 degrees, this concoction reflects objects back at any angle. In other words, a device such as this would make aircraft, boats and satellites entirely easier to track with radar, but it'll have to mature quite a bit before it's ready for that kind of action. The current build is just a single centimeter high and ten centimeters in diameter, and as with invisibility cloaks, the main ingredient here is metamaterials that we won't pretend to fully understand. Just one word of caution, boffins -- don't let Geek Squad get ahold of this stuff.[Image courtesy of Barbara Rich, thanks JR]
Cloaking device puts the kibosh on cellphone interference
There has been plenty of research into cloaking devices, but while scientists are still working their way towards the visible light spectrum they seem to be having the best luck with microwaves. Most recently, a new metamaterial made from over 10,000 individual pieces of fiberglass has been used to cloak a bump on a flat mirrored surface -- the material prevents microwaves from being scattered, giving the RADAR (we're guessing it's a RADAR) the impression that the surface is flat. This has many possible applications, such as cloaking sources of interference to cellular communications. Unfortunately, the implication we most desire -- rendering us invisible during high society jewel heists -- has yet to become reality.
Researchers create light bending material for invisibility cloak
We're only at the nano scale folks so you'll have to keep those high school fantasies of an invisibility-cloaked romp through the girls' locker room tucked away for now. Still, two teams of US government funded researchers under the direction of Xian Zhanga at UC Berkeley say that they've developed a material which can bend visible light around 3D objects, effectively making them disappear. While similar to the negative refractive properties of materials developed back in 2006, UCB's so-called meta-material is easier to work with and absorbs far less light than those earlier products. As such, the material could scale to the size of invisibility cloaks to hide objects such as tanks or mischievous boy-wizards. However, that day is a long ways off. In the short term, the meta-material will most likely find use in the far less interesting (to consumers, anyway) application of building better microscopes. Hey, Xian, picture of your invisible material or it didn't happen... oh, wait.[Via BBC News]
Researchers develop metamaterial with negative refractive index
We've got next-to-invisible objects and cameras with ridiculously large sensors, and thanks to a team of brilliant researchers over in Germany, now we've got "an exotic material with a negative refractive index for visible light." Gunnar Dolling and his colleagues at the University of Karlsruhe in Germany have created a metamaterial with layers of silver sandwiching a thin sliver of nonconducting magnesium fluoride on a glass sheet, and once an array of square holes were etched in, his tests showed that the "structure had a negative refractive index of -0.6 for light with a wavelength of 780-nanometers," besting the previous record of 1,400-nanometers. While the scientific babble may not mean much to you, the long and short of it is that this discovery could "lead to further breakthroughs in invisibility cloaks, which could hide objects from the human eye" and make escaping your troubles quite a bit easier. Moreover, the technology could be used in "superlenses" to see details "finer than the wavelength of visible light," but Dolling is reportedly more interested in studying the effects of his discovery than attempting to build any mystical devices, which is probably for the good of mankind, anyway.[Via Slashdot]
Japanese researchers invent completely transparent material
In a breakthrough that could benefit fields as diverse as networking, photography, astronomy, and peeping, science-types at Japan's Institute of Physical and Chemical Research have unveiled their prototype of a glass-like material that they claim to be 100% transparent. Unlike normal glass, which reflects some of the incoming light, the new so-called metamaterial --composed of a grid of gold or silver nanocoils embedded in a prism-shaped, glass-like material -- uses its unique structural properties to achieve a negative refractive index, or complete transparency. Although currently just a one-off proof-of-concept (pictured, under an electron microscope), mass-produced versions of the new material could improve fiber optic communications, contribute to better telescopes and cameras, or lead to the development of completely new optical equipment.
