Clarke envisioned more than two decades ago. The technology will be put into practice by NASA, where researchers are exploring the possibility of using nanotubes to make a space elevator, something like the 23,000-mile satellite-to-Earth cable Arthur C. "We do know that nanotubes can carry about 100 times the current that would destroy an ordinary electronic interconnector." "Carbon nanotubes carry an extremely high current and carry it with such extremely little resistance, it's possible they carry current as well as it can be carried - at its quantum limit," says Johnson, who leads a team of researchers in the department of physics and astronomy. Charlie Johnson at the University of Pennsylvania says he's most bullish about how nanotubes will improve electrical interconnectors. "I don't expect that, overnight, people will say, 'OK, let's drop silicon, and from now on we'll use nanotubes.' "Īvouris says nanotubes may be introduced commercially in the next few years - first in niche applications and then perhaps in devices where silicon and nanotubes are mixed. "Silicon has reached a very high level of sophistication, and there is a tremendous infrastructure built around silicon," he explains. Given the amount of money that's been invested in competing technologies, Avouris says, he doesn't expect a speedy race to make nanotubes the building material of the next generation of electronics. And the demand hasn't caught up with the buzz nanotubes are creating in university physics departments and at places like IBM. And their atomic arrangement can be adjusted to make them behave as metals or semiconductors."īut even if the technological properties "are extremely good," Avouris says the introduction of nanotubes will be slow because of cost and other factors. They have outstanding thermal conductivity. They can take 100 times the current as metallic wires.
"Nanotubes have wonderful qualities that make them intriguing. "Everything is really at the beginning stages," says Phaedon Avouris, manager of IBM's nanometer scale science and technology. Many engineers see nanotubes as an alternative to silicon, the medium in which transistors, diodes and other semiconductor device structures are usually built today. They also have the highest and most stable electron emissions rate recorded, researchers say. Extremely small electrical wires could make use of nanotubes' electricity- and heat-conducting capabilities to make computer circuits smaller and faster. Nanotubes could also have many other uses. you don't need a big power supply, and the whole package becomes much smaller." "Basically, the current on conventional monitors requires a high voltage, and you need a big power supply to do that," says Fang. in Korea, which has demonstrated a display screen in which electrons are fired at the screen from nanotubes, estimates that it's just two years away from bringing nanotube screens to market. Nanotube monitors will be so svelte, they'll be hung like posters, according to Fang. The reason, Fang says, is simple: Carbon nanotubes have a very low field-emission voltage, which means lower voltage is needed to emit the electrons that produce an image. in Lexington, Ky., convinced that nanotechnology will be used in monitors within five years.
Such attributes have scientists like Shaoli Fang, a vice president at CarboLex Inc. They can also emit electrons, so they can be used in ultrathin display screens. Nanotubes are stronger than metal because the chemical bond holding them together is stronger.īut nanotubes have other qualities that are whetting the appetites of engineers: They're excellent conductors of electricity and heat, and they can be used as wires, semiconductors or superconductors. They consist of concentric shells of graphite, with each shell rolled into a cylinder so the lattice of carbon atoms remains continuous. They're microscopic tubes made of a remarkable form of soot and have chemical properties that make them stronger than steel and lighter than plastic. in Japan in 1991, when he was investigating the residue deposited during a process that synthesized fullerenes (a molecular form of pure carbon noted for its cagelike structures). And there are chat rooms dedicated to the latest nano scuttlebutt on the futuristic chat site So, what are these nanotubes anyway, and why are they generating such interest?Ĭarbon nanotubes were discovered by electron microscopist Sumio Lijima at NEC Corp. Enthusiasts with names like "Nanoboy" and "Nanogirl" have set up Web sites. For a technology that's years away from practical application, nanotubes have acquired a cultlike following.
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