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Photonics: Although iron pyrite, otherwise known as iron sulfide or fool's gold, was tossed aside by miners more than a century ago, it may prove to be worth its weight in gold as a thin-film solar cell material. Researchers at Oregon State University have found that iron pyrite, which contains two of the most abundant elements on Earth, is an excellent absorber of solar energy and can be made into extremely thin layers. Unfortunately, the substantial heat required to create solar cells causes the pyrite to decompose. So the researchers tried an inverse design approach. "We identified the failure mechanism of pyrite, formulated a few design rules that preserved the favorable aspects of pyrite, and identified [iron silicon sulfide] and [iron germanium sulfide] as new absorber candidates," said Douglas Keszler, coauthor of a paper published in Advanced Energy Materials. But much more work remains to be done. It could take at least 10 more years to fine-tune a marketable alternative to traditional solar cell materials.

New Scientist: Jalila Essaïdi, a "bioartist" in the Netherlands, recently worked with an international team to blend spider silk with human skin to try to produce a bulletproof material. The project, called 2.6g 329m/s, involved a Utah State University team, which genetically engineered goats to produce spider-silk proteins in their milk. Researchers in South Korea and Germany spun the proteins and wove them into a fabric, which was then wedged between bioengineered skin cells by a biochemist at Leiden University in the Netherlands. In making the material, Essaïdi, who uses biology and life sciences as an artistic medium, says she wanted "to explore the social, political, ethical and cultural issues surrounding safety in a world with access to new biotechnologies." According to the artist, safety is a relative concept, as demonstrated by the "bulletproof" shield she constructed from the hybrid material, which succeeded in stopping a partially slowed bullet, but not one traveling at full speed.

Daily Mail: Researchers at the University of Texas at Austin have succeeded in cloaking a three-dimensional object. According to their results published today in the New Journal of Physics, the group used plasmonic metamaterials to hide an 18-cm cylindrical tube illuminated by microwave radiation. Plasmonic metamaterials scatter light rays differently from the way more common materials do. "When the scattered fields from the cloak and the object interfere, they cancel each other out and the overall effect is transparency and invisibility at all angles of observation," said Andrea Alù, one of the study’s coauthors. One of the next challenges will be to demonstrate cloaking in visible light.

New York Times: The chrome look is making a comeback for automobiles, writes Tudor Van Hampton for the New York Times. However, rather than actual chrome, which is expensive and heavy, manufacturers are using materials that mimic chrome. One such material has been produced by Hamlin Jennings, a cement scientist at MIT who has developed a process to coat aluminum with a thin layer of glass. The glass chemically fuses to the metal, producing the look of polished chrome and protecting the surface from scratches and oxidation. The process will probably be used mainly in luxury vehicles for trim around windows and headlights. For most purposes, a good-quality shiny plastic is just as effective and much less expensive.

Discover: Researchers have genetically modified silkworms to produce a hybrid silk that’s partly from silkworm and partly from spider. Spider silk is extraordinarily strong and tough and can stretch several times its original length. Farming spiders has not proven as practical as farming silkworms, however, because spiders are territorial and cannibalistic. So Donald Jarvis and Randy Lewis of the University of Wyoming and Malcolm Fraser of the University of Notre Dame inserted spider silk genes into the silk-making glands of silkworms. Although the new silk is only 2–5% spider silk, it is stronger, more elastic, and twice as tough as normal silkworm fiber. Spider silk could have many uses, such as in sutures, artificial ligaments, and body armor.

ScienceDaily: Researchers at Purdue University have designed V-shaped gold and silicon nanoantennas that can cause broadband light to bend in unusual ways, including with negative angles of refraction. Extending earlier work by a group at Harvard University, the Purdue team showed that an array of the nanoantennas at a material interface can change the phase and propagation direction of light over a broad range in the near-IR. The arrays, much thinner than the light’s wavelengths, produced dramatic deviations from the conventional laws governing how light refracts as it passes from one material to the next. Says team member Vladimir Shalaev, "Not only the bending effect, refraction, but also the reflection of light can be dramatically modified by the antenna arrays on the interface, as the experiments showed." Shalaev is the scientific director of nanophotonics at Purdue's Birck Nanotechnology Center and one of the authors of a paper published online yesterday in Science. The team’s technique could have a range of technological applications, including in fiber-optic telecommunications and in more powerful microscope lenses.

BBC: The first computer chip made of molybdenum disulfide has been tested by Andras Kis of the Laboratory of Nanoscale Electronics and Structures in Lausanne, Switzerland, and colleagues. Known as molybdenite, MoS₂ is a naturally occurring mineral that's less reactive than silicon and can therefore be used in thinner layers to make smaller, more flexible, more energy-efficient chips. Unlike graphene, another material that can be used in flexible semiconductors, MoS₂ can amplify electronic signals at room temperature, whereas graphene has to be cooled to 70 kelvin to do so. Kis and his colleagues say that despite MoS₂'s potential, it could be 20 years before it's ready for commercial use. They plan to explore the possibility of making it more conductive in the meantime.

Daily Mail: Researchers at the University of Cambridge in the UK have created a graphene-based ink and used a modified Epson printer to produce thin-film circuits, writes Ted Thornhill for the Daily Mail. To create the ink, they dissolved microscopic flakes of graphite in N-methylpyrrolidone. Although printed electronics aren’t new, the Cambridge team replaced the metal nanoparticle inks with graphene, which is lighter, cheaper, more conductive, and more stable. The flexible electronics created from such ink-jet printing could be used in touch screens, photovoltaic devices, and electronic textiles. The group describes the technique in a paper submitted to the arXiv e-print server.

Talking Points Memo: Researchers at HRL Laboratories, Caltech, and the University of California, Irvine have created the world’s lightest material—ultralight metallic microlattice. The researchers poured a liquid material into the microlattice pattern and hardened it by exposing it to UV light, writes Carl Franzen for Talking Points Memo. Electroless nickel—an alloy of nickel and phosphorous—was then poured onto the pattern very precisely, forming a 100-nanometer-thin uniform coating. The resulting material is 99.99% air and has a density of only 0.9 mg/cc. Much lighter than Styrofoam, it floats to the ground like a feather when dropped, according to William Carter of HRL, one of the authors of a recent Science paper on the subject. However, it is the structure itself that is important, not the material it is made from. According to Carter, his team can “make the same structure out of many different materials,” including polymers and ceramics. Developed for the Defense Advanced Research Projects Agency, such ultralight cellular materials could be used in thermal insulation, batteries, and acoustics.

Shareable: Here is a novel use for three-dimensional printers: producing shells for hermit crabs. Because they don’t make their own shells (they scavenge shells made by other creatures) and because the worldwide shell supply is diminishing, the crabs have been forced to use other objects instead, such as bottles and shotgun shell casings. Makerbot Industries, which produces build-it-yourself 3D printer kits, has launched Project Shellter to inspire members of the Makerbot community to design and produce the ideal hermit crab home. As inspired and inspiring as the project sounds, however, critics point out that a better solution would be for humans to stop destroying seashells in the first place. They also warn that the world’s oceans already contain too much plastic.

National Geographic: A glass-like carbon allotrope that's been used for 30 years in chemistry and electronics has recently been found to become hard as diamond under high pressures. Ho Kwang Mao, of the Carnegie Institution of Washington, and colleagues slowly applied pressures—similar to those found hundreds of kilometers below Earth's crust—to the allotrope, which under normal conditions is made almost entirely of flat bonds, like graphite. Under pressure, the bonds changed from flat to three-dimensional and crystalline, which gave the substance a diamond-like hardness. When the pressure was released, the material returned to its pliable glassy form, its bonds flat once more. Although it's too soon to know what commercial uses could be found for the reversible carbon, it could potentially be used in laboratories to apply high pressure to a material from many sides at once.

ABC News: Researchers at the University of Texas at Dallas have succeeded in creating a working cloaking device; they published the details this week in the journal Nanotechnology. For their device Ali Aliev and colleagues made a porous sponge out of sheets of carbon nanotubes, which are known for their exceptional ability to conduct heat and transfer it to surrounding areas. When a steep temperature gradient is imposed on the sponge, the refractive index of the surrounding air also acquires a steep gradient. Light rays are bent away from an object, just as in a desert mirage, and make the object seem invisible. The researchers have posted a video of their device in action in the lab.

BBC: Self-healing materials—whether metal, plastic, or a carbon composite—have been around for almost a decade. Now Nancy Sottos and coworkers at the University of Illinois at Urbana-Champaign have developed a new, nature-inspired technique, which they describe in the Journal of the Royal Society Interface. It involves impregnating plastic with a fine network of channels, each less than 10^-8 meter in diameter, which can be filled with liquid resin, writes Leila Battison for the BBC. The microvascular networks spread out in the material to function much like an animal’s circulatory system, supplying the healing agent to all areas. Syringes on the outside of the material put the liquid resin under constant pressure so that when a crack appears, the pressure drives the fluid into it. Materials that could repair themselves as they crack would have many uses, including in civil engineering.

R&D Magazine: Stacking up three layers of graphene can significantly modify its electrical properties, according to research at the University of California, Riverside. Depending on how the three layers are stacked, some structures are conducting and some are insulating. Graphene is a one-atom-thick sheet of carbon atoms, arranged in hexagonal rings. Its most stable, conducting form occurs when one corner of the hexagons of the middle sheet is located above the center of the hexagons of the bottom sheet, and the top sheet is exactly on top of the lowest sheet, forming what's called a Bernal-stacked trilayer, or ABA pattern. If the top sheet is shifted by the distance of a single atom, to a rhombohedral-stacked trilayer, or ABC pattern, the trilayer arrangement becomes insulating. "Why this happens is not clear as yet. It could be induced by electronic interactions. We eagerly await an explanation from theorists!" said Jeanie Lau, one of the authors of a Nature Physics paper on the subject.

BBC: While researchers have been making advances toward developing a Harry Potter–style invisibility cloak containing metamaterials that guide light waves around the cloak's wearer, a group in Spain has designed a "cloak" that renders the wearer invisible to magnetic fields, according to a paper published in the New Journal of Physics. Because light and magnetism are two facets of the same physical force, many of the same principles apply. Thus Alvaro Sanchez and coworkers at the Autonomous University of Barcelona have developed an antimagnet, which uses an inner cloak of superconducting material, surrounded by layers of metamaterials whose response to the magnetic field varies in a prescribed way through the thickness of the cloak, writes Jason Palmer for the BBC. Their device could have many uses, including protective shielding of pacemaker wearers during MRI scans.

New York Times: China's near total monopoly on the rare-earth market, is forcing foreign manufacturers of high-tech materials to move their production to China. Those that don't must contend with uncertain supplies and higher prices. The restrictions are an attempt by the Chinese government to increase the number of high-tech companies in the country and to encourage technology transfer to local Chinese-owned corporations. "We saw the writing on the wall--we simply bought the equipment and ramped up in China to begin with," said Mike Pugh, director of worldwide operations for Intermatrix, who told the New York Times the company would have preferred to build its new factory near its California headquarters.

The move seems to be directed by Premier Wen Jiabao, a former geologist who studied rare earth minerals at graduate school. Denying international access to materials to favor local production may make China in breach of regulations established by the World Trade Organization, of which it is a member. The European Union is considering taking China to court once a related case is finally resolved.

Chemical and Engineering News: A team of chemists at Rice University has shown how to prepare graphene from everyday materials, including grass, a cockroach leg, bulk polystyrene, chocolate, and even Girl Scout cookies. As detailed in a paper published online at ACS Nano, James Tour and colleagues placed a solid sample on copper foil in a quartz boat and briefly heated the material to 1050 °C under a low-pressure hydrogen–argon flow. Graphene formed on the back side of the foil, while a residue of other elements remained on the sample side. Graphene has been touted as a miracle material for its toughness and conductivity since its discovery by Nobel Prize–winning scientists Andre Geim and Konstantin Novoselov. Tour, who wanted to show that graphene can be made from just about anything with carbon, hopes that production costs will drop quickly as commercial interests develop methods to manufacture it in bulk.

Daily Mail: A research team at the University of Nottingham campus in Ningbo, China, has developed a material that, when applied to the walls of a room, allows them to absorb and store excess heat and release it later. Jo Darkwa and Oliver Su said the phase-change material, or PCM, will work as a spray, forming a microscopic film on surfaces. When the air in a PCM-treated room rises above a certain temperature, the particles in the spray absorb the excess heat and melt, but instead of dripping they are held in place by a special coating. When the room temperature decreases, the material becomes a solid, releasing the heat back into the room. Darkwa and Su believe the material could both save energy and reduce carbon emissions.

MSNBC: Zvonimir Dogic of Brandeis University and his colleagues have performed an experiment that helps solve a biological mystery: how cilia, the microscopic hairs that sprout from certain cells, beat together to perform such useful tasks as expelling mucous from lungs and ferrying eggs from ovaries into the uterus. Dogic's team made artificial cilia from just three components: microtubule filaments, motor proteins called kinesin, and a bundling agent. Although the artificial cilia lacked a dedicated internal means to communicate with each other, the researchers found that the cilia spontaneously beat together under certain external conditions. The simplicity of the artificial system could lead to nonbiological applications.

Science Daily: A University of Georgia researcher has invented a new technology that can render natural and synthetic materials, such as clothing and medical linens, permanently germ-free. Jason Locklin developed the antimicrobial treatment to kill a wide spectrum of bacteria, yeasts, and molds that can cause disease, create stains, and produce odors. It is inexpensive and can be applied to textiles using solution casting or spray coating either during or after the manufacturing process, and it remains fully active after multiple hot-water laundry cycles. Thin films of the new technology can also be used to change other surface properties of both cellulose- and polymer-based materials, including color, reflectance, absorbance, and iridescence. Locklin, who has published his results in Applied Materials and Interfaces, expects the process to be of special benefit to healthcare facilities and hotels, which are prone to the proliferation and spread of very harmful microorganisms.

BBC: Researchers have been working on a new technology to decontaminate water in developing countries. It involves coating grains of sand with an oxide of graphite, a widely available material commonly used as pencil lead. Sand has been used to purify water since ancient times. Although fine sand is more effective than coarse when cleaning water of pathogens, organic materials, and heavy metal ions, water drains much more slowly through fine sand than coarse. "Our product combines coarse sand with functional carbon material that could offer higher retention for those pollutants, and at the same time gives good throughput," explained Wei Gao of Rice University, one of the authors of a study published in Applied Materials and Interfaces. In addition, lead scientist Pulickel Ajayan, also at Rice, said the graphite oxide could be modified to make it more selective and sensitive to certain pollutants. Because the necessary materials are cheap and readily available and the graphite-coated sand grains can be synthesized using room-temperature processes, the researchers say the method would be very cost efficient.

Science News: Scientists have spun a multitude of high-tech materials into bundles of superfine nanowires that are more than 1000 meters long, writes Rachel Ehrenberg for Science News. Although trimming big, bulky materials down to nanosize has proven difficult in the past, Mehmet Bayindir of the Institute of Materials Science and Nanotechnology at Bilkent University in Turkey and colleagues have succeeded in doing so with a solid rod of material wrapped in polymer. They heated the rod, drew it out in a long micrometers-thick thread, cut that into 15-cm lengths, consolidated the lengths into a bundle, and heated and spun that into even finer thread. Not only are the wires they produced exceedingly long, they are also homogeneous. The new technique, reported online in Nature Materials, produces uniform, orderly arrays of gossamer-thin materials that could have broad use in sensors, energy-harvesting devices, and medical diagnostics.

New Scientist: Three new stable carbon allotropes have been revealed by simulation, writes MacGregor Campbell for New Scientist. To find out whether forms of carbon denser than diamond might be possible, Artem Oganov of Stony Brook University in New York and colleagues simulated different configurations of carbon atoms at different temperatures and pressures. They found three that seemed to be stable enough to be made. While the three new allotropes are not as hard as diamond, their greater density would give them a higher refractive index and thus greater sparkle than diamond. Each of the three has unique band gaps, with one of them, tP12, having the largest band gap of any form of carbon; this variability makes them potential candidates for superconductors. It's unclear as yet how the new materials could be made, although Oganov thinks that some of the unidentified, distinct carbon configurations produced by "shock compression" of graphite and amorphous carbon may be the newly described allotropes.

Science News: A beam of light shining on the left side of a normal piece of glass or plastic will pass through and reflect exactly the same as a beam of light shining on the right side. Nonlinear materials interact with light in a very different way; light changes the properties of such materials as it passes through them, and those changes affect the behavior of the light itself. As a result, the frequency of light that can pass through those materials depends on the direction of the light. Giulio Casati, of the University of Insubria in Como, Italy, and Stefani Lepri, of the Italian National Research Council for Complex Systems in Florence, mathematically modeled the behavior of light passing through two layers of such material and described a way to transmit about 80% of the light traveling in one direction while blocking about 70% of the light coming from the opposite direction. This selectivity could be used in the creation of wave diodes. Traditional diodes allow electric current to flow in one direction, and a wave diode could allow light to flow in one direction in quantum or optical computer applications. The model may also apply to acoustical applications of nonlinear materials.

Wired: The first desktop model of the Big Bang is sitting on a bench at the University of Maryland's College Park campus. Igor Smolyaninov and Yu-Ju Hung, both electrical engineers at UMD, made the simulation from metamaterials, substances that use alternating slices of different materials to twist light in unusual ways. They arranged strips of acrylic and gold so that when laser light hits the gold, it excites waves of free electrons called plasmons.The plasmons' path through the metamaterials' flat surface is mathematically the same as the movement of massive particles after the Big Bang. The model could allow physicists to study the thermodynamic arrow of time and the cosmological arrow of time in ways that have been impossible previously. Smolyaninov described the model in a paper submitted to Physical Review Letters. Chen Sun, a mathematical engineer at Northwestern University, expressed both interest in the model and some doubt as to whether the plasmons' path through it is truly analogous to the expansion of the universe.

Science News: A new way to manipulate atoms inside diamond crystals so that they store information long enough to function as quantum memory is being developed, writes Devin Powell for Science News. But the scientists involved aren’t looking for perfect diamonds, rather for ones with defects. One of the most common defects in diamond is nitrogen, which turns the stone yellow. When a nitrogen atom sits next to a vacant spot in the carbon crystal, the intruding element provides an extra electron that moves into the hole. Several years ago, scientists learned how to change the spin of such electrons using microwave energy and put them to work as quantum bits, or qubits. Diamond memory has several advantages: It works at room temperature, it’s very stable, and it can be scaled up to larger sizes. David Awschalom of the University of California, Santa Barbara, discussed the technique at the American Physical Society’s March meeting in Dallas, Texas.

New Scientist: Like their counterparts in science fiction, the robots that make cars and other objects are rigid devices whose limbs are driven by stiff pistons and other mechanical actuators. Electroactive polymers (EAPs) can mimic the flexible, flexing action of human muscles, offering engineers a way to make robots more versatile and lifelike. Now, a team from the Auckland Bioengineering Institute's Biomimetics Lab in New Zealand has demonstrated that EAP-based muscles can not only produce lever-like contraction; they can also, when suitably configured, produce rotary motion. The advance makes possible new kinds of robots beyond the factory assembly worker or the humanoid companion.

NPR: Nanodiamonds—clusters of a few hundred carbon atoms—may find a use in the treatment of cancer. Researchers at Northwestern University infected lab mice with chemo-resistant breast and liver cancers and then tested two treatments. Mice that were injected with nanodiamonds covered in the drug doxorubicin fared better than those given unbound doxorubicin. Nanodiamond-bound doxorubicin tends to stick around in mice up to 10 times longer than unbound doxorubicin does, leading to a slower, more sustained therapy. The high retention of the nanodiamonds within tumors means that smaller, less harmful doses can be used. As nanodiamonds are already in use in the automotive industry as a lubricant, they are mass-produced and don’t cost much. The results of their work appear in the latest issue of Science Translational Medicine.

New York Times: Researchers have for years been trying to replicate spiders’ silk for use in many different products. Spiders’ silk is not a single material but varies from sticky toothpaste-like mush to strong, stretchy draglines and can be stronger than steel or bulletproof like Kevlar. Recent applications by Tufts University researchers include electrode arrays that are printed on flexible, degradable silk films, which may one day be used to treat epilepsy without producing the scarring that larger implanted electrodes do, and a coil made of silk substrate and gold that can help tell when food goes bad. Yet some of the qualities of actual spiders' silk, such as the complex ways proteins in natural silk are folded to give each silk its unique properties, still elude researchers.

Science: The exoskeletons of ants, ticks, and other arthropods, both ancient and modern, are made up of proteins, sugars, and calcium carbonate. When an arthropod dies, microbes begin eating the first two components of the shell. The upshot for paleontologists is that little of an ancient arthropod's exoskeleton survives as a fossil. But some exoskeleton does survive, and now, as Science's Sid Perkins reports, we know why. George Cody of the Carnegie Institution of Washington and his collaborators applied x-ray absorption near edge structure (XANES) spectromicroscopy to the fossilized remains of two arthropods, a 310-million-year-old land scorpion and a 417-million-year-old sea scorpion. Comparison with modern scorpions revealed that what remained of the fossilized exoskeletons had been chemically modified, possibly by chemicals from the exoskeleton's original waxy coating. When the scorpions were alive, the waxy coating prevented their exoskeletons from drying out. When they died, the coating decomposed, releasing chemicals that stabilized the exoskeleton's protein–sugar complex.

Nature: Laying one kind of semiconductor nanowire athwart another kind of semiconductor nanowire creates a tiny transistor. Arranging multiple nanowires in a grid-like fashion creates a device that can perform elementary logic. That's what Harvard University's Charles Lieber and his collaborators have done. Reporting in today's Nature, Lieber describes making and operating "logic tiles" that consist of 496 transistors and measure 960 μm² in area. The tiles' programming ability arises from the crossings' configuration and from the sequence in which the wires are activated.

New Scientist: The elusive goal of integrating lasers and electronics has come a big step closer with the first growth of nanoscale lasers directly on silicon. Silicon itself is a poor laser material. The tiny lasers are made instead from indium-gallium-arsenide, which is usually hard to grow directly on silicon. In a paper published in Nature Photonics, Connie Chang-Hasnain of the University of California, Berkeley, and her colleagues describe a novel growth scheme that overcomes the integration roadblock.

Los Angeles Times: Fool's gold, or iron pyrite, may one day provide a cheap alternative to the rare, toxic, and expensive materials now used for making solar panels, according to a group of researchers at the University of California, Irvine. The UCI team believes the mineral can be processed into a thin film for use in photovoltaic cells, and could eventually convert sunlight into electricity at roughly the same rate as existing technology. Skeptics warn, however, that commercializing the process is difficult because, in order to be successful, hundreds of thousands of panels must be produced each year, at a cost that can compete with Chinese prices.

New Scientist: Nanotechnologists have developed conducting fabrics that can survive a washing machine, reports Paul Marks for New Scientist. Researchers at the University of Texas at Dallas, who have published their results in Science, have been experimenting with nanotube yarns peppered with “guest” particles wrapped up in a tightly scrolled web. Besides use in clothing, the technique could have other engineering applications, such as in batteries and supercapacitors.

New Scientist: Researchers in Japan used a new electron microscope, whose beams of electrons have about 40% less energy than those in previous studies, to make measurements of the fragile bonds in carbon atoms on the edge of a sample of graphene. In the past, only high-energy beams were available, which could disturb the bonds on delicate lone atoms. The team could resolve the number of bonds holding the edge carbon atoms in place, which is important because it can affect the graphene sheet’s electrical and chemical properties. Their findings were published in Nature yesterday.

New York Times: The US Department of Energy released a report today that examines the extent to which the development and use of clean energy in the US depends on access to rare earths and other critical materials, some of which are produced abroad. The report's main conclusions, quoted from the executive summary, are that

• Several clean energy technologies—including wind turbines, electric vehicles, photovoltaic cells and fluorescent lighting—use materials at risk of supply disruptions in the short term. Those risks will generally decrease in the medium and long term.
• Clean energy technologies currently constitute about 20 percent of global consumption of critical materials. As clean energy technologies are deployed more widely in the decades ahead, their share of global consumption of critical materials will likely grow.
• Of the materials analyzed, five rare earth metals (dysprosium, neodymium, terbium, europium and yttrium), as well as indium, are assessed as most critical in the short term. For this purpose, “criticality” is a measure that combines importance to the clean energy economy and risk of supply disruption.
• Sound policies and strategic investments can reduce the risk of supply disruptions, especially in the medium and long term.
• Data with respect to many of the issues considered in this report are sparse.

In a news story about the report, the New York Times's Keith Bradsher points out that China produces more than 90% of the world's rare earths. As if to underscore its hold on the rare-earth market, China announced yesterday that it would raise export taxes on some rare earths next year.

New York Times: In his blog Pogue's Posts, New York Times technology reporter David Pogue uncovers the surprising history of Gorilla Glass, the environmentally friendly alkali-aluminosilicate thin-sheet glass used for the touchscreens of smartphones. Corning invented the material in the 1960s, but didn't find an application for it until Apple's Steve Jobs performed an impromptu test on a sample: He put it in his pocket and jostled it against his keys.

Daily Mail: Researchers at MIT are investigating the possibility of using a rare metal, ruthenium, that can absorb sunlight, store the energy, and release it as pure heat to create a “rechargeable heat battery.” When molecules of fulvalene diruthenium absorb sunlight, they change shape into a long-lived semistable state. When the molecules interact with a catalyst, they snap back into their original form, releasing heat. Such a system could be far more effective than conventional solar-thermal ones, which require insulation and gradually lose heat. The drawback is the metal’s rarity—ruthenium comes from the same family as platinum.

Nature: A high-profile graphene researcher, Walt de Heer of the Georgia Institute of Technology, has written to the Nobel Prize committee for physics, objecting to errors in its explanation of this year's prize, writes Eugenie Samuel Reich in Nature. De Heer sees a series of errors that he believes overplay the significance of prize recipients Andre Geim and Konstantin Novoselov's work at the expense of other researchers. He also claims that other mistakes downplay the work of Philip Kim of Columbia University, whom many researchers think should have shared the prize. The committee is now correcting several points in its document raised by De Heer's letter.

New York Times: Chinese shipments of lanthanum, neodymium, and other rare-earth elements appear to have restarted, reports Keith Bradsher of the New York Times. In a show of strength that lacked an officially avowed motive, the Chinese government had blocked the export of the industrially important minerals to Japan on 21 September and to Europe and the US on 18 October. Although the Chinese gave no explanation for the resumption, Bradsher noted that

The decision came a day and a half after Secretary of State Hillary Rodham Clinton announced plans to visit China on Saturday. She met on Wednesday in Honolulu with Japan’s foreign minister, Seiji Maehara, and said afterward that the suspension of shipments had been a “wake-up call” and that both countries would have to find alternative suppliers.

Washington Post: This year's physics Nobel went to Andre Geim and Konstantin Novoselov for discovering in 2004 how to make graphene, a two-dimensional form of carbon. The discovery excited physicists and engineers because of graphene's superb electrical and mechanical properties. Writing in the Washington Post, Brian Palmer examines when those properties will prove profitable. The main source of delay lies in finding a way to make the material cheaply and in large batches. Palmer concludes:

As chic as graphene is today, it's still really a material of the future. But there's so much money and excitement in graphene research, the future may be soon.

Nature: During the English Civil War (1641–52), a warship, thought to be the Parliamentarians' Swan, sank off Scotland's west coast. Among artifacts retrieved from the wreck in the 1990s was a barnacle-encrusted pocket watch. Now, thanks to a compact CT scanner built by X-Tek Systems of Tring outside London, a team from the National Museum of Scotland has peered through the barnacles to discover the watch's movement. Jo Marchant's report for Nature includes a movie that presents a "fly through" view of the CT data.

New York Times: For three weeks, Hitachi, Sony, and other Japanese electronics companies have not received any shipments of lanthanum, neodymium, and other rare earths from China. The export embargo, thought to be provoked by Japan's arrest at sea of a Chinese trawler captain, is neither acknowledged nor documented, which, as the New York Times's Keith Bradsher explains, makes it hard for Japan to respond through the World Trade Organization and other official channels. Trade officials in Japan, the US, and other countries are considering alternative methods for dealing with what could become a threat to their economies.

Daily Mail: Recent advances in nanotechnology could turn Willy Wonka’s Three-Course Dinner Chewing Gum into reality. In Roald Dahl’s 1964 novel Charlie and the Chocolate Factory, the gum first tastes like tomato soup, then roast beef and baked potato, and finally blueberry pie and ice cream. Now, food scientist Dave Hart and coworkers at the UK’s Institute of Food Research (IFR) say they have cracked the secret behind creating such a stick of chewing gum. Hart and his team are experimenting with creating different flavor layers separated by a tasteless gelatin, with a final dessert taste at the center, encapsulated in a high-tech gel called Gellan. “Tiny nanostructures within the gum would contain each of the different flavors. These would be broken up and released upon contact with saliva or after a certain amount of chewing,” says Hart.

The Tennessean: Arnold Burger and fellow Fisk University researchers have just made it easier for Homeland Security agents to tell the difference between a dirty bomb and a banana.

Fruit, such as a banana contains potassium, which can give off the same radiation signature as plutonium.

The Fisk researchers, in partnership with Radiation Monitoring Devices Inc, and Lawrence Livermore and Oak Ridge National Laboratories, have developed a cheaper, easy-to-produce, new type of radiation-detecting crystal that is more accurate than most of the devices on the market.

The group has just won an R&D 100 magazine award, given to the 100 cleverest inventions of the year for their work.

Daily Mail: Researchers at the University of California, Berkeley, have developed a touch-sensitive artificial "skin"—dubbed "e-skin"—made of thin flexible material embedded with inorganic semiconductor nanowires. According to Ali Javey, head of the Berkeley research team, ''The idea is to have a material that functions like the human skin, which means incorporating the ability to feel and touch objects." The material could be used on robots and perhaps even on humans with artificial limbs, which would require more sophisticated techniques involving integration of electronic sensors with the human nervous system. The group has published its findings in Nature Materials.

New York Times: Certain materials change their resistance in response to a change in voltage. That simple switching behavior, which arises from the material itself, could form the basis of new, compact computer memory—provided the material is cheap, robust, and convenient to use. In the New York Times, John Markoff reports a recent development toward that goal. Jun Yao of Rice University and his collaborators have built a switch out of silicon dioxide, a bedrock material of current computers whose resistive switching was previously unsuspected. Markoff also reports that an independent team from Hewlett-Packard is set to announce an advance toward the same goal but with a different "memristor" technology.

New York Times: It’s long been appreciated that the vivid colors of butterfly wings arise not from pigments, which selectively absorb certain frequencies, but from intrinsic microstructures, which selectively refract certain frequencies. Now, Yale University’s Richard Prum and his collaborators have figured out how those microstructures grow as the butterfly develops inside its chrysalis.

Nature: An elastic polymer has been made whose molecular structure mimics that of titin, a protein found in muscle. The resulting material is tough and stretchy and dissipates energy — just like muscle itself.

New Scientist: To get complicated nanostructures on a silicon chip it is sometimes necessary to grow them in separate layers and then transfer these one by one onto the final chip (PDF) to build them into working components.

Often it takes strong chemicals to separate the layers from the surface on which they are grown, and high temperatures may be needed to activate the thermal adhesives that keep the components in place at their destination.

Grégory Schneider and Cees Dekker at the Kavli Institute of Nanoscience in Delft, the Netherlands, have found a way to use water to quickly and easily transfer layers from one surface to another. They exploit the fact that different materials have different hydrophilicity—the tendency to attract water through transient hydrogen bonds.

Various: Updated 4/16/2010: A number of outlets have written articles about the societal impact of volcanic ash caused by this week's eruption in Iceland.

Various: Hewlett-Packard scientists last week announced a new advancement in memristors or memory resistors. They were theoretically conceived in 1971 by Leon O. Chua, an electrical engineer at the University of California, Berkeley, but they were not put into practical effect until 2008 at an HP lab.

Memristors are simpler than today’s semiconducting transistors, but can store information even in the absence of an electrical current.

The new breakthrough, published in Nature, is that a memristor can perform logic steps, potentially enabling computation to be performed in chips where data are stored.

Related news pick
Big advance reported in memory chip design

Related links
From lab to fab—An HP Labs discovery demonstrates the viability—and versatility—of memristor technology HP press release
‘Memristive’ switches enable ‘stateful’ logic operations via material implication Nature
HP labs outlines breakthroughs in memristor chip research eWeek
HP sees a revolution in memory chip New York Times

Various: Lightning is typically associated with rain clouds and thunderstorms, which leads to an unusual observation, why is there lightning in the middle of the desert? Or in plumes of volcanic ash?

The answer may lie in a new theory by Thomas Pähtz, Hans J. Herrmann, and Troy Shinbrot, in Nature Physics.

They suggest that particles transfer electrical charge vertically when the particles are smashed together, such that positive charges move downward and negative charges move up in the cloud.

Although the theory explains how the particles develop charge, it doesn't explain the origin of the external electrical field needed to kick off the charging process.

Related links
Why do particle clouds generate electric charges?
Swirling dust shocks physicists NatureNews
Colliding dust grains charge each other up ScienceNews

New Scientist: Pure diamond is a super-tough electrical insulator, but given the right impurities it becomes a semiconductor. Crucially, it is also the best thermal conductor on Earth. Those properties means synthetic diamond could be used to make microchips that handle high-power signals but do not require power-hungry cooling systems.

"Diamond-based control modules in electric cars and industrial machinery could lead to considerable energy savings," says Hideaki Yamada of National Institute of Advanced Industrial Science and Technology (AIST) in Tsukuba, Japan.

Physics Today: NASA, US Navy and university researchers have successfully demonstrated the first robotic underwater vehicle to be powered entirely by natural, renewable, ocean thermal energy, that can be scalable to a wide range of autonomous crafts capable of virtually indefinite ocean monitoring for climate and marine animal studies, exploration and surveillance.

NYTimes.com: Blas P. Uberuaga, Xian-Ming Bai, and colleagues at Los Alamos National Laboratory in New Mexico have shown that by altering the microstructure of metals, metallurgists may be able to make nuclear reactor parts that are self healing.

Their conclusions are based on computer simulations of the long-term impact of neutron emissions on copper—not because much copper is used in nuclear plants, but because it is a relatively well-modeled metal.

Cracks in the internal parts of reactors are a big concern both to the nuclear power plant operators (who want to keep maintenance costs low, and any repairs that require shutting the reactor down cost a lot of money), and to regulators (who want to make sure that radioactive material doesn't leak into the environment).

Related link
Efficient annealing of radiation damage near grain boundaries via interstitial emission

Science: Have you noticed that computers have stopped getting faster?
Microprocessor clock frequencies plateaued around 2005, a stunning break after a decades-long run of ever-compounding improvements in computing speed.

The cause is a breakdown of the simple constant-electric-field scaling rules that had guided the shrinking of field-effect transistors for decades. As transistors shrank, they switched faster and used less power to switch but a certain amount of power is still needed to switch them from ON to OFF and vice versa.

Companies continue to shrink the transistor, emphasizing the increasing number of parallel processors (cores) they can place on a single silicon chip. But with power supply voltages stuck at about 1 V, increasing clock frequencies as in the past would result in unsupportable increases in power dissipation and heat generation. The transistor is rapidly approaching its ultimate physical limits.

The only way to decisively break the power dissipation bottleneck is to change the physics of transistor operation in ways that facilitate further reduction of operating voltage says Thomas N. Theis and Paul M. Solomon in Science.

Wall Street Journal: Bill Watkins, the former CEO of hard-disk drive maker Seagate Technology, wants to shake up the prices of solid-state light-emitting diodes.

Watkins became CEO of LED maker Bridgelux in January. On Tuesday, the Sunnyvale, California, company released a product called Helieon that Mr. Watkins says will cost as low as $20 for a lighting unit that has a lifespan of more than 10 years.

While $20 may seem like a lot for a lightbulb, Mr. Watkins says the price is less than half of the $50 that has been standard for similar LED lighting systems.

Science: The exceptional properties of many materials often come at the expense of limited performance in other areas. For example, conventional metals and their alloys are strong--they are good at resisting stress (i.e., an applied load)—but they tolerate only a very small amount of strain (i.e., deformation) before they are irreversibly deformed. Rubber can easily return to its original shape, even after large deformations, but is much weaker than conventional metals.

However, some metal alloys exhibit "shape memory"; they are strong but can recover from being deformed when heated.

This process seems counterintuitive, but these alloys take advantage of solid-to-solid "diffusionless" phase transitions: The atoms rearrange how they pack into crystals in an orderly fashion, and this process changes the material's macroscopic shape.

Few other materials possess this combination of strength and flexibility, and clever engineering has exploited these properties--for example, in implanted medical devices such as stents. In Science, Y. Tanaka and associates report on a superelastic alloy that almost doubles the useful range of deformation that can be induced in such alloys.

Related link
Ferrous polycrystalline shape-memory alloy showing huge superelasticity

Nature: The golden ratio—n exact 'magic' number often claimed to be observed when taking ratios of distances in ancient and modern architecture, sculpture and painting—has been spotted in a magnetic compound.

Science: In the past decade, there has been an explosion of academic and industrial interest in the use of organic conducting ("pi-conjugated") materials in optoelectronics, flexible logic circuits, light emission, energy conversion, optical communications.

Compared with inorganic materials, pi-conjugated materials can more easily be tuned through molecular design and cost less to manufacture.

Advances in physical understanding, synthetic control of the chemical product, and computational molecular design now allow pi-conjugated materials to be tailored for a specific purpose or function. In Science, Joel M. Hales and associates report a promising new approach to the design of pi-conjugated materials for all-optical communications.

Related link
Design of polymethine dyes with large third-order optical nonlinearities and loss figures of merit

Various: Andrew Cleland, John Martinis, and colleagues at the University of California, Santa Barbara, have provided the first clear demonstration that the theory of quantum mechanics applies to the mechanical motion of an object large enough to be seen by the naked eye. Their work satisfies a longstanding goal among physicists.

The Economist: Between 1992 and 2007, according to Lawrence Livermore National Laboratory physicist Ian Hutcheon, 17kg of highly enriched uranium was seized from smugglers around the world, along with 400 grams of plutonium.

In neither case is that enough for a proper atom bomb, but it is still worrying says the Economist.

Presumably, more is out there. Even if it is not, the material that has been found could have been used to make a “radiological” weapon, by blowing it up and scattering it around a city using conventional explosives.

Hutcheon is one of those charged with analyzing this captured material, to discover how dangerous it really is and where it came from.

Physics Today: Heat is the bane of computer manufacturers as it places severe limits on how fast computer chips can run. Some computer systems, such as Intel's Pentium desktops, have fans that blow cool air onto the circuit boards. Other solutions, which usually involve supercomputers, include dipping the entire computer in a fast-moving fluid to keep the equipment cool.

But what if we could design a liquid cooling system that could be built onto the silicon chip?

Chunlei Guo and Anatoliy Vorobyev at the Institute of Optics at the University of Rochester have come up with one technique that could be applied to create such a system.

Their paper in Optics Express describes how to make liquid flow vertically upward along a silicon surface, overcoming the pull of gravity, without pumps or other mechanical devices, through strong capillary action.

It works by carving nanometer-scale structures in silicon, with extremely short, high-powered laser bursts. These grooves increase the attraction or hydrophile that water molecules feel toward the silicon. The attraction becomes so great that it overcomes the strong bond that water molecules feel for other water molecules.

So instead of sticking to each other, the water molecules climb over one another for a chance to be next to the silicon. The water rushes up the surface at speeds of 3.5 cm per second, fast enough to allow any desktop computer chip with this design to run substantially hotter than traditional computer chips.

Related link
Laser turns silicon superwicking

Nature News: If quantum computing networks are ever to become a reality, physicists must find a way to direct and harness the light emitted in quantum experiments without using cumbersome apparatus.

Now Holger Hofmann, at the Department of Quantum Matter at Hiroshima University in Japan, and his colleagues have developed a way to control the direction of light on the nanoscale. Their technique is based on the workings of the Yagi-Uda antenna commonly used to transmit and detect shortwave radio waves.

Nature News: Using a special trap, researchers have captured and weighed three isotopes of the superheavy element nobelium—the heaviest element so far to have its mass measured directly.

Science: The first superconductors were discovered in 1911. Half a century passed before physicists came up with a theory that could explain why some compounds had zero resistance at a few degrees above absolute zero. In 1986, researchers discovered complex compounds nicknamed "cuprates" containing copper and oxygen that become superconductors at much higher "critical temperatures"—now as high as 138 kelvin, but couldn't explain how or why they worked.

In the last couple of years, researchers have discovered a new type, four families of iron-based superconductors with distinct crystal structures, that superconduct at temperatures as high at 27 Kelvin. Using tools honed on the cuprates they have made measurements that took decades to achieve in the older materials.

More importantly, although physicists cannot say exactly how the iron-based superconductors work, they have developed a scheme that many say captures the essence of what's going on. "We don't have a full solution yet," says MIT theorist Patrick Lee, "but the situation is better than in the cuprates."

In fact, the emerging portrait of the iron-based superconductors jibes with some theories of the cuprates and seems to undermine more-exotic alternatives. So if physicists are on the right track with the iron-based superconductors, then the cuprates may not be so inscrutable after all.

Science News: Recent studies show that the oceans may hold more “garbage patches” of fine plastic flotsam than scientists realized and that the fragments extend well below the sea surface.

Most of these items are the size of fingernail clippings or smaller. They are the wave-shattered remnants of items such as rubbish, abandoned fishing gear and floats from fishing nets and scientific instruments. These plastic bits are especially common in a region of the Pacific Ocean southwest of California that is sometimes called the Great Pacific Garbage Patch.

Recent cruises reveal that there’s more garbage in this patch than often meets the eye, oceanographer Giora Proskurowski of the Sea Education Association in Woods Hole, Mass., reported February 24 at the American Geophysical Union’s Ocean Sciences meeting.

The Economist: Ludvig Edman of Umea University and Nathaniel Robinson of Linkoping in Sweden may have found a way to tweak organic light-emitting diodes, or OLEDs, by blending the semiconducting polymer with potassium trifluoromethylsulfonate. The result is a sheet similar to wallpaper that can illuminate itself at the flick of a switch.

redOrbit: Unless you're interested in isotopic labeling, neutrons don't figure much into chemistry. Neutral in charge and a bit bigger than a proton, the neutron neither gives an atom its name nor determines much about its reactivity.

But neutrons have some unsung properties that make them useful for investigating matter. Because they are neutral, they can penetrate deeper into a sample than electrons can. Because they have mass and spin, they have a magnetic moment and can probe magnetism. Because they interact with nuclei rather than electron orbitals, they are sensitive to light elements and can even distinguish between hydrogen and deuterium. And they're nondestructive. These features are inspiring researchers to use neutrons to analyze a variety of materials, from coal and complex fluids to cell membranes and membrane proteins and including magnetic materials.

The Economist: The great hope of transplant surgeons is that they will, one day, be able to order replacement body parts on demand. That possibility may be closer with the arrival of the first commercial 3D bio-printer for manufacturing human tissue and organs.

The new machine, which costs around $200,000, has been developed by San Diego–based Organovo, a company that specializes in regenerative medicine, and an Australian engineering and automation firm called Invetech.

To start with, only simple tissues, such as skin, muscle, and short stretches of blood vessels, will be made for research purposes.

Organovo expects that within five years, once clinical trials are complete, the printers will produce blood vessels for use as grafts in bypass surgery.

optics.org: The first IR-emitting germanium laser has been created by researchers in the US. The development could be an important step towards creating optical components such as lasers from silicon—which like germanium is an indirect-gap semiconductor—rather than direct-gap materials such as indium phosphide.

Science: The different colors on the surface of a soap bubble arise from the interference of light waves reflecting from the outer and inner surface of the liquid film. As the thickness of the film varies, so will the wavelength of light that undergoes constructive interference and remains visible.

According to quantum mechanics, even material particles such as electrons behave like waves. In addition to their charge, electrons also have two distinguishable spin states, spin-up and spin-down.

In Science, Petta and associates demonstrate beam splitting and interferometry for the spin degrees of freedom of two electrons on a semiconductor chip.

Related link
A coherent beam splitter for electronic spin states

NYTimes.com: The America’s Cup has always been a showcase for innovation: The 1895 victor, Defender, for example, used aluminum, steel, and bronze in the hull, an unheard–of combination at the time. And sailing in general, and high-level racing in particular, are no strangers to technology. But it has not been used at such an extreme scale before.

The most obvious advance can be seen rising above USA-17, which is owned by Lawrence J. Ellison, president of the software company Oracle. It looks as if someone wrenched a wing off a large jetliner and perched it, tip up, atop a trailer hitch on the boat’s middle hull.

Related Physics Today articles
The physics of sailing February 2008
Sailing and the physics of lift (letters about the previous article) September 2008
Ship hydrodynamics June 1978

Physics Today: IBM researchers demonstrated a radio-frequency graphene transistor with the highest cut-off frequency achieved so far for any graphene device—100 billion cycles/second (100 gigahertz).

The high frequency record was achieved using wafer-scale, epitaxially grown graphene using processing technology compatible to that used in advanced silicon device fabrication.

"A key advantage of graphene lies in the very high speeds in which electrons propagate, which is essential for achieving high-speed, high-performance next generation transistors," said T. C. Chen, vice president of science and technology, IBM Research. "The breakthrough we are announcing demonstrates clearly that graphene can be utilized to produce high performance devices and integrated circuits."

Graphene is a single atom-thick layer of carbon atoms bonded in a hexagonal honeycomb-like arrangement. This two-dimensional form of carbon has unique electrical, optical, mechanical, and thermal properties, and its technological applications are being explored intensely.

Uniform and high-quality graphene wafers were synthesized by thermal decomposition of a silicon carbide (SiC) substrate.  The graphene transistor itself utilized a metal top-gate architecture and a novel gate insulator stack involving a polymer and a high dielectric constant oxide. The gate length was modest, 240 nanometers, leaving plenty of space for further optimization of its performance by scaling down the gate length.

The frequency performance of the graphene device already exceeds the cut-off frequency of state-of-the-art silicon transistors of the same gate length (~ 40 GHz).  

Nature Physics: A new detailed analysis of the melting point of diamond suggests that Neptune and Uranus could contain liquid diamond oceans.

Measuring the melting point of a diamond is very difficult because usually when it's heated to very high temperatures diamond changes to graphite. To get round this researchers applied extremely high levels of pressure to diamonds and blasted them with lasers to reach 50,000 degrees—similar to temperature and pressure conditions found in the outer planets.

When diamond is melted it behaves like water during freezing and melting, with solid forms of diamond "icebergs" floating atop liquid forms.

Related article
Diamond: Molten under pressure

The Economist: Electromagnetic pulses (EMPs) are usually associated with warfare.

In a less extreme fashion, however, EMPs have peaceful uses. They are already employed industrially to shape soft and light metals, such as aluminum and copper.

Now a group of researchers at the Fraunhofer Institute for Machine Tools and Forming Technology in Chemnitz, Germany, has found a way to use an EMP device to shape and punch holes through industry’s metallic heavyweight—steel. This could transform manufacturing by doing away with the need to use large, heavy presses to make goods ranging from cars to washing machines.

New Scientist: A complex 248-dimensional symmetry called E₈ has been glimpsed in laboratory experiments on exotic crystals.

Radu Coldea of the University of Oxford and his colleagues chilled a crystal made of cobalt and niobium to 0.04 °C above absolute zero. Atoms in the crystal are arranged in long, parallel chains. Because of a quantum property called spin, electrons attached to the atom chains act like tiny bar magnets, each of which can only point up or down.

Applying a 5.5-Tesla magnetic field perpendicular to the direction of the electrons create spontaneous patterns in the electron spins in the chains, some of which match the E₈ structure.

Related link
Quantum Criticality in an Ising Chain: Experimental Evidence for Emergent E₈ Symmetry

Physics Today: Los Alamos National Laboratory has conducted its first-ever double-viewpoint hydrodynamic test of a nuclear weapon component mockup at LANL's Dual Axis Radiographic Hydrodynamic Test (DARHT) facility.

DARHT has been operational for 10 years on one axis, but using a second axis simultaneously is a milestone for the facility. 

The test is part of the National Nuclear Security Administration's stockpile stewardship program to continue to maintain the viability of US nuclear weapons without having to resort to underground nuclear tests.

"This is an important development," said Brig. Gen. Garrett Harencak, NNSA principal assistant deputy administrator for military application. "The multiple X-ray images provided by [DARHT] will inform the critical work of our scientists and engineers across the nuclear security enterprise."

"Initial indications show excellent data return," said the hydrodynamic experiments division leader, David Funk.  "The baseline experiment captured five time-dependent X-ray images and a variety of data from other diagnostics of pressure, temperature, and timing.  This data provides the nation with one of the most rigorous tests of our capability to predict [nuclear] weapons performance."

Conducted inside a specially designed double-walled containment vessel, the test used high explosives to drive an implosion of a duplicate of a W78 nuclear warhead made from non-nuclear surrogate materials.  As the mockup is imploding, the DARHT facility fires two electron accelerators positioned at a 90-degree angle from one another to generate high-power x-rays that are used to create multiple images of the imploding device's inner workings, which are then compared with computer predictions.

The DARHT team solved a variety of technical challenges in the months and years leading up to this experiment.  "While the first axis of DARHT has been functioning nearly flawlessly for more than 10 years, the second axis is still an operational prototype of the world's longest pulsed electron linear accelerator, so the challenges have been monumental," said Funk.  "Just fitting the accelerator in the building had its challenges, leading to the use of a novel material with an exceptionally high magnetic field strength. Using standard materials would have required the accelerator to be five times bigger than it is, and it would not have fit in the building."

Other challenges included designing a cathode injector system that would supply enough electrical current to the accelerator and developing a target that is robust enough to survive four pulses from the extremely high-energy electron beam of the second axis.

"I couldn't be more proud of our team's accomplishments preparing and conducting this first test," said Funk.  "The test marks the beginning of what will be a very long operational lifetime for this important diagnostic tool in support of national security."

cleveland.com: In the labs and wind tunnels of NASA's Glenn Research Center and three other NASA facilities—Langley, Dryden, and Ames—the prospect of commercial supersonic flight is quietly coming out of mothballs. 

The back-to-basics plan lacks the hype of the government's three previous high-speed flight research efforts, which touted a future of large American-produced commercial supersonic fleets but failed to produce a viable design. 

"The programs in the past...were setting targets that were very audacious, to say the least," said Jay Dryer, director of NASA's Fundamental Aeronautics Program, of which supersonics research is a part. "I think we're going in with a more realistic expectation of what's possible, yet we're still pushing the state of the art." 

This time, NASA is taking an incremental approach. It intends to pave the way for small faster-than-sound "low-boom" business jets by 2015, 35- to 70-passenger commercial jets by 2020, and quiet airliners with the capacity and Mach 2 speed of the Concorde sometime after 2030.
 
"It's the next step in the evolution of the transportation system," said Glenn engineer Louis Povinelli, the supersonics project's senior technologist and chief scientist. "It's inevitable."

Nature: Electrical injection and detection of spin-polarized electrons in a silicon chip have now been demonstrated at room temperature, paving the way to the development of low-power semiconductor spintronics circuitry.

Science: Jet turbine engines have benefited from decades of development of nickel-based superalloys, which have allowed a steady increase in engine operating temperatures and led to improved performance and efficiency.

However, operating temperatures are now reaching limits posed by the melting temperatures of these materials.

New materials, including alloys based on metals with higher melting points, such as molybdenum (Mo) and niobium (Nb) alloyed with silicon (Si), are now being seriously examined as alternatives by academic and industrial groups.