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Oddly, even though some predict it will be a $1 trillion industry in a decade, there's no good definition for the field, other than saying it involves manipulating materials at the nano scale.

It's such a new field that the name itself is just beginning to catch on. For example, James Harper, professor of physics and director of the Materials Science Program, lists more than a dozen research papers on his Web site concerning thin-film work, a staple of this field, yet only the most recent has the prefix "nano" in the title. It's not that researchers weren't working on nanoscale projects, he explains, it's just that they're not used to their work having applications in nanotechnology.

Harper's research deals with the reactions and properties of films, sometimes just a few atoms thick, when placed on other materials. This is the sort of basic research that will be UNH's strength in the new center.

"One of the challenges is to have materials with different properties exist very close to each other—for example, a metallic conductor with an insulator—and keeping their good qualities separate while shrinking them down as far as possible," Harper says. "The smaller you get, the harder it is to keep the properties separate."

Some of the "thin" films that James Harper, director of the UNH Materials Science Program, applies are just a few atoms thick.

This hurdle is typical of nanoscale work because it takes something that is well-understood on the everyday scale—applying films of material is what you do every time you paint the living room—and tries to make it work in the atomic world.

"We have hundreds of years of experience with materials in bulk form, but many of those properties don't tell you how they're going to behave at the atomic level. That's where the interesting physics come in: We're dealing with so few atoms that they behave differently; they aren't seeing themselves as part of a continuous material anymore," he says. "It can be very surprising."

In theory, nanotechnology has been possible since the 1920s, when Max Planck, Niels Bohr, Werner Heisenberg (whose son, Jochen, is a professor of physics at UNH) and others developed the theory of quantum mechanics, which defines the laws of physics that apply on very small scales. But nanotechnology only became a realistic goal in the past two decades after the development of the scanning tunneling microscope and subsequent devices that can not only see things as small as atoms, but can pick them up and move them as well.

The public first became aware of this ability in 1986, when IBM spelled out its logo with a handful of xenon atoms. "Some people consider that the beginning of nano-technology," says Miller. "It didn't really do anything useful, but it showed what could be done."

Karsten Pohl could spell out UNH with atoms if he wanted to, since he oversees UNH's atomic-resolution scanning tunneling microscope. Worth a quarter of a million dollars, the UNH-built microscope is one of the most expensive pieces of equipment on campus. With it, Pohl and his graduate students can make images of atoms and manipulate them at very low temperatures, thanks to bubbling vats of liquid nitrogen. They are also working on making templates for the alignment of nanotubes.

UNH is big into nanotubes. As the name implies, nanotubes are tiny cylindrical tubes, often made of carbon atoms, held together by atomic bonds. The hollow tubes have a number of interesting properties, including enormous strength ("nanoVelcro" made of tangled nanotubes is a potential replacement for glue) as well as the potential to conduct electricity.

A tiny tube that conducts electricity is a nanowire, a vital part of nanosized electrical components such as computer memory chips—hence the great interest.

"The microprocessing industry, the Intels of the world, create a commercial driving force for going smaller," says Miller. When creating computer chips, "there are limits with existing technology, and chip manufacturers are closing in on fundamental barriers," he notes. "But now they envision bottom-up techniques, where you start with small molecules and build up those features you want through guided self-assembly."

In the research world's Darwinian struggle for laboratory space, equipment, professorial salaries and students, the importance of a rich driving force cannot be overemphasized. In computers, smaller is also faster, and both are known commodities that sell. As a result, no one is saying "this is all pie-in-the-sky stuff," says Miller. "Not when Intel is involved."

There are, of course, problems—big problems. For one thing, nanotubes are easy to make but hard to make correctly. "No two nanotubes are alike. Nanotubes are single-walled, multi-walled, straight and curved, with large and small diameters," says Miller. This uncertainty comes about because they are currently created at high temperatures—at least 600 degrees Celsius—where "all hell breaks loose" at the atomic level.

Low temperatures are needed for nanotubes, says Miller.

"Right now, no technology exists that will produce a batch of nanotubes that are exactly alike. That's not good enough: Industry wants to be able to call a vendor and say, 'I want a billion conducting nanotubes, each 63 nanometers long and two nanometers wide and straight as an arrow.'" Miller's efforts to design new low-temperature processes that will make uniform batches of identical carbon nanotubes are funded with grants from the National Science Foundation and the Army.

But electronics isn't the only application for nanotechnology. Part of Claverie's work is figuring out whether nanoparticles can be used in paints to make them more environmentally friendly. That's a far cry from the sci-fi type of projects which get the most attention—such as the idea of using nanotubes to build an elevator into space—but Claverie says it's typical and more realistic.

"Many applications are going to be much more low-cost and less spectacular than people think, but important nonetheless," he says. "I don't do spectacular things—I don't do little spaceships inside the body," he adds, giving a nod to Isaac Asimov's 1966 science-fiction book Fantastic Voyage, where people are miniaturized and injected into a man's bloodstream to destroy a clot.

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