Tiny Tubes Could Absorb More Carbon Dioxide Than Trees - Environment. Smallest-Ever Nanotube Transistors Outperform Silicon. The smallest carbon-nanotube transistor ever made, a nine-nanometer device, performs better than any other transistor has at this size. For over a decade, researchers have promised that carbon nanotubes, with their superior electrical properties, would make for better transistors at ever-tinier sizes, but that claim hadn’t been tested in the lab at these extremes.
Researchers at IBM who made the nanotube transistors say this is the first experimental evidence that any material is a viable potential replacement for silicon at a size smaller than 10 nanometers. “The results really highlight the value of nanotubes in the most sophisticated type of transistors,” says John Rogers, professor of materials science at the University of Illinois at Urbana-Champaign.
“They suggest, very clearly, that nanotubes have the potential for doing something truly competitive with, or complementary to, silicon.” Several major engineering problems remain, says Franklin. Tiny Tubes Could Absorb More Carbon Dioxide Than Trees - Environment. Engineers build first sub-10-nm carbon nanotube transistor. (PhysOrg.com) -- Engineers have built the first carbon nanotube (CNT) transistor with a channel length below 10 nm, a size that is considered a requirement for computing technology in the next decade.
Not only can the tiny transistor sufficiently control current, it does so significantly better than predicted by theory. It even outperforms the best competing silicon transistors at this scale, demonstrating a superior current density at a very low operating voltage. The engineers, from the IBM T.J. Watson Research Center in Yorktown Heights, New York; ETH Zurich in Zurich, Switzerland; and Purdue University in West Lafayette, Indiana, have published their study on the first sub-10-nm CNT transistor in a recent issue of Nano Letters. Many research groups are working on reducing the size of transistors in order to meet the requirements of future computing technology for smaller, denser integrated circuits.
Explore further: Shiny quantum dots brighten future of solar cells. Engineers weld nanowires with light. At the nano level, researchers at Stanford have discovered a new way to weld together meshes of tiny wires. Their work could lead to innovative electronics and solar applications. To succeed, they called upon plasmonics. One area of intensive research at the nanoscale is the creation of electrically conductive meshes made of metal nanowires. Promising exceptional electrical throughput, low cost and easy processing, engineers foresee a day when such meshes are common in new generations of touch-screens, video displays, light-emitting diodes and thin-film solar cells. Standing in the way, however, is a major engineering hurdle: In processing, these delicate meshes must be heated or pressed to unite the crisscross pattern of nanowires that form the mesh, damaging them in the process.
Self-limiting At the heart of the technique is the physics of plasmonics, the interaction of light and metal in which the light flows across the surface of the metal in waves, like water on the beach. Transparency. Scientists Use Carbon Nanotubes to Create an Underwater Invisibility Cloak. University of Dallas scientists have found a way to fashion carbon nanotubes, the same material used to improve displays and solar panels, into an invisibility cloak. Scientists discovered that if they heated the tubes underwater they could create a “mirage effect” to make objects completely disappear. It’s really that simple. All the scientists had to do was setup a sheet of one-molecule-thick carbon nanotubes sheets and apply an extreme amount of heat--we’re talking a maximum of 2,500 degrees Kelvin (2,300 degrees Celsius).
No big deal, right? The carbon nanotube creates a mirage in the same way the beating sun on a hot summer day makes it look like the sky is part of the street. (Mirages are created by light bending in an upward concave arc as hot air rises, so when you see the sky as part of the ground, your eyes are actually sensing an image from the bent photons.)
[IOP Science via io9] Like this? Scientists have used carbon nanotubes to engineer the most powerful artificial muscles ever. Artificial gravity, if you spin the station at the top you won't need to worry about bone loss etc. due to the low gravity environment. Yeah! That's a good idea! Muscles to drive the spin of a station. No it doesn't. You're not being imaginative enough. We could hook these artificial sinews to a grasping ratchets around a drum assembly with the drum fixed to the space elevator itself. There'd be some torsional issues but these would be tiny in comparison to the mass of the elevator cable itself. It's times like this I wish I could draw pictures, post them here and clarify what I mean or imagine.
Scientists grow nanowire directly on a crystal — and help usher in the next generation of electronics. Carbon Nanotubes Used to Stitch Materials Together. 0inShare Engineers at Massachusetts Institute of Technology devised a method to use carbon nanotubes as a stitching material for composites. Because nanotubes could be made into some of the strongest known fibers, the technology should allow the development of new generation of medical prostheses and novel medical materials. Wardle wondered whether it would make sense to reinforce the plies in advanced composites with nanotubes aligned perpendicular to the carbon-fiber plies.
Using computer models of how such a material would fracture, “we convinced ourselves that reinforcing with nanotubes should work far better than all other approaches,” Wardle said. His team went on to develop processing techniques for creating the nanotubes and for incorporating them into existing aerospace composites, work that was published last year in two separate journals. How does nanostitching work? The polymer glue between two carbon-fiber layers is heated, becoming more liquid-like. Nanotube Cables Hit a Milestone: As Good as Copper. For the first time, researchers have made carbon-nanotube electrical cables that can carry as much current as copper wires. These nanotube cables could help carry more renewable power farther in the electrical grid, provide lightweight wiring for more-fuel-efficient vehicles and planes, and make connections in low-power computer chips.
Researchers at Rice University have now demonstrated carbon-nanotube cables in a practical system and are designing a manufacturing line for commercial production. Making lightweight, efficient carbon nanotube wiring as conductive as copper has been a goal of nanotechnologists since the 1980s. Individual carbon nanotubes—hollow nanoscale tubes of pure carbon—are mechanically strong and an order of magnitude more conductive than copper. But unless carbon nanotubes are put together just so, larger structures made from them don’t have the superlative properties of the individual tubes. Perfect nanotubes shine brightest: Researchers show how length, imperfections affect carbon nanotube fluorescence. A painstaking study by Rice University has brought a wealth of new information about single-walled carbon nanotubes through analysis of their fluorescence.
The current issue of the American Chemical Society journal ACS Nano features an article about work by the Rice lab of chemist Bruce Weisman to understand how the lengths and imperfections of individual nanotubes affect their fluorescence -- in this case, the light they emit at near-infrared wavelengths. The researchers found that the brightest nanotubes of the same length show consistent fluorescence intensity, and the longer the tube, the brighter. "There's a rather well-defined limit to how bright they appear," Weisman said. "And that maximum brightness is proportional to length, which suggests those tubes are not affected by imperfections.
" But they found that brightness among nanotubes of the same length varied widely, likely due to damaged or defective structures or chemical reactions that allowed atoms to latch onto the surface. Nanotube growth theory experimentally confirmed. (PhysOrg.com) -- The Air Force Research Laboratory in Dayton, Ohio, has experimentally confirmed a theory by Rice University Professor Boris Yakobson that foretold a pair of interesting properties about nanotube growth: That the chirality of a nanotube controls the speed of its growth, and that armchair nanotubes should grow the fastest.
The work is a sure step toward defining all the mysteries inherent in what Yakobson calls the "DNA code of nanotubes," the parameters that determine their chirality -- or angle of growth -- and thus their electrical, optical and mechanical properties. Developing the ability to grow batches of nanotubes with specific characteristics is a critical goal of nanoscale research. The new paper by Air Force senior researcher Benji Maruyama; former Air Force colleague Rahul Rao, now at the Honda Research Institute in Ohio; Yakobson and their co-authors appeared this week in the online version of the journal Nature Materials.
Yakobson, Rice's Karl F.