Nanotechnology fast approaches realization

In Neal Stephenson’s 1995 novel, “The Diamond Age,” he wrote of a not-too-distant future where the world is run with nanotechnology. Nano- is the metric prefix for one-billionth; a nanometer, abbreviated nm, is one-billionth of a meter. This is a good deal smaller than most cells and only a factor of 10 larger than the average diameter of an atom.

The huge problems associated with working at this level make it seem that Stephenson’s descriptions of molecule-sized wheels whose spokes can sort out pollutants from water, credit cards implanted in the skull making money obsolete, and matter that can arrange itself into anything from a book to an island seem like the wildest fantasy. Yet, in 1865, Jules Verne was labeled a madman for describing a trip to the moon, a prediction that became fact little more than a century later. A look at the history of nanotechnology strongly suggests that it will take far less than a century to make it a part of our lives.

Nanotechnology became more than a theoretical pipe dream when scientists at IBM developed the scanning, tunneling microscope that allowed them to “see” individual atoms. The researchers publicized the new device by using it to spell out “IBM” using 35 xenon atoms arranged on a nickel surface. This admitted publicity stunt took place in 1990 but, since then, many other experiments have shown the potential for nanotechnology.

In 1998, Sandia National Laboratories in New Mexico developed a working electromagnetic combination lock so small it could fit on the period at the end of this sentence. The lock has movable shafts and gears and is being designed to prevent computer intrusions.

Also in 1998, engineers at the Technion-Israel Institute of Technology made a silver wire just 100 nm in diameter that successfully carried an electric current. In effect, the wire assembled itself from individual silver atoms by aligning them with the electrostatic charge on a DNA strand. What makes this of particular significance is that it is one of the first working devices made by self-assembly.

In September 2000, a group of German chemists was able to synthesize a complex organic molecule from two simpler ones by using the scanning telescope to aid them in removing specific atoms from the molecules and joining the free ends together. An example of how far miniaturization has come, a working guitar only 2 millionths of a meter in length is considered too large to be true nanotechnology.

The Nov. 24 issue of Science carried a series of articles on the current status of nanotechnology. In the introduction, editors remark on a similar 1991 issue taken up mainly with speculation and predictions. Today the situation is far different.

Nanotechnology research centers are springing up around the world, the U.S. Congress has allocated $423 million to start up a National Nanotechnology Initiative, and computer disk drives, with sandwiched layers of materials on a nanometer scale, have become a multibillion-dollar industry. Richard Smalley, the Nobel Prize-winning chemist who invented the nanometer-sized carbon cages known as buckyballs, said he hopes the rapidly developing field of nanotechnology will stimulate a new interest in science among American students.

Harvard University chemist George Whitesides said it now is possible to take matter as individual atoms and assemble it to make almost anything desired. But, he warns, what is possible on an atomic level may prove much harder to do on a larger scale. For example, a group in the Netherlands made a transistor from carbon nanotubes in 1998 that outperformed the standard silicon ones. When it came to putting millions of the nanotubes on a computer chip, however, “it turned out to be completely unmanufacturable.”

This is where the science of nanotechnology is now. The rapid development of single microscopic devices that work either in theory or practice but have proved extremely difficult to scale up to practical use. And some critics of nanotechnology are in no hurry for the breakthrough to working scale devices to come any time soon. In the April 2000 issue of Wired, Bill Joy, who is the cofounder of Sun-Microsystems in California, warned that nanotechnology, along with biotechnology and robotics, could spell disaster for the planet.

Clair Wood taught chemistry and physics for more than 10 years at Eastern Maine Technical College.