Tech Talk
How does Nanotechnology work?
Nanotechnology: The Molecular Assembly Line By: Andy Shaw Imagining the workings of nanotechnology – the often-astonishing technology of the invisibly small – isn’t hard. Picture a robotic arm picking up a tool and applying the tool to an object while it’s moving past. Then the arm swings back, shelves the tool, picks up a new tool, and returns to the passing gizmo to complete the next assembly step. Easy enough to see in your mind’s eye – it’s just like advanced manufacturing we know today. And indeed, nano-engineers are now at work designing prototypes for such tiny robots, or “assemblers” as they’re known in the nanotech trade. But here’s the hard part to imagine. Such assemblers are molecular in size – only tens of nanometers long, wide, and high. So small they will build things one atom at a time. A thousand such assemblers hooked together in a factory line would barely stretch across a human hair. A nanometer, after all, is only a billionth of a meter. Well, if the assembler is so small, you might ask, what could it possibly make for our day-to-day world where useful stuff is more often measured in meters? SELF-REPLICATING SELF-REPLICATORS Because, in theory, you can link a few billion of those molecular assemblers together and program them to replicate themselves and build ever bigger self-replicating assemblers. Then you could make just about anything better, cheaper, and faster than you’d ever dreamed. From flawless sheet metal to videocams and skyscrapers. And you’d have such control over these massed assemblers that you could make your new stuff without producing a drop of toxic waste. What’s more, two other branches of the technology – nano-computing and nano-engineering – promise to make your new creation smart and super strong. Just how smart and strong was revealed to this writer during a recent week long tour of nanotechnology research labs and companies in Switzerland, where nanotechnology has been put at the heart of Swiss economic development. At IBM’s renowned Zurich Research Laboratory, for instance, Mark Lantz, a Canadian research scientist from Edmonton, is developing a “millipede” chip. It’s nanometric dimensions are so small it can’t be seen by regular microscopes but only through a scanning tunnel microscope (STM), another IBM Zurich Lab invention. The chip is based on the same electro-sensitive cantilever arm technology that forms images for the STM. In the chip, sharp tips on more than a 1000 cantilever arms poke holes in a polymer sheet, storing digital information just as today’s silicon chip does. But the millipede chip is 1,000 times smaller. THE SPACE ELEVATOR In a parallel effort at a Swiss technical university, the …Ecole Polytechnique Federale de Lausanne (EPFL), physicists and research engineers are investigating use of another small miracle of nanotechnology, carbon nanotubes. “You can place single atoms inside these tubes and it gives materials wonderful properties,” says Dr. Laslo Forro, head of the EPFL’s Physics of Complex Matter Institute. New nanotube-based materials can be at once flexible as rubber and as hard as diamonds. It’s been speculated that such material could form cables for a “space elevator” that would run supplies up to an orbiting station. Since nanotubes can also be made into semiconductors, they or millipede chips could be invisibly blended or woven into a host material. So car bodies could mend their own dents or change color, and clothes could clean themselves, heat or cool, and alter their size – all that the whim of the driver or the wearer. Nanotechnology computers are so minuscule that researchers at the University of California and elsewhere are developing “smart dust”. Within motes of this dust will ride the sensors, processors, networking, and power supply needed to make clouds of smart dust do the bidding of its developers. That might lead to the most effective pesticide ever invented, or if consumed with your cereal, the best picture of your innards to ever emerge but, as some experts fear, it also might lead to a new weapon of war, cast with murderous intent over a battlefield. A GRAY GOO WORLD So there is a dark side to nanotechnology. Science fiction writers have been making much lately of assemblers running amok and turning the world into a mass of gray goo. And nanotechnology has its scientific skeptics. Some scientists believe that the machine-like assembler described above simply won’t work. They know that at the nano level things don’t behave quite like they do in the macro world. The physics change and becomes less predictable because it’s where the much more chaotic quantum mechanics begin to take over. Yet nature itself has shown that nanotechnology does work, at least in biology. The human cell is an exquisite nanostructure capable of self-replicating and assembling the most complex and intelligent structure we know of in the universe. So the bet is that the nanotechnology, now just in its infancy, will be multi-disciplinary as it matures, needing the skills not just of the engineer, but the physicist, the biologist, and the chemist. Recognizing this, leading educational institutes such as the EPFL in Lausanne, are changing curricula, fusing engineering with life sciences. PLENTY OF ROOM FOR INNOVATION While some nanotech products have already been commercialized including super slick, self-cleaning coatings for glass and super sensitive gas detectors, most nanotechnology is still in the research stage. The kind of mass production nano-fabrication systems described here is still a long way off most experts agree. Yet it is clear nanotechnology holds great promise. It is the most energized field of industrial research at the moment. Last year, the Canadian government committed $120 million to a new National Institute of Nanotechnology in Edmonton. The U.S. similarly spent $420 million and worldwide nano research spending is nearly $2 billion annually. All confirming a vision of Nobel prize winner Richard Feynman once had of the opportunity for innovation there is way down where things are small, when he said: “There’s plenty of room at the bottom.” Andy Shaw is a freelance writer whose work appears frequently in Canadian business and high tech publications.
