JOIN USNano scheme of things
“I would like to describe a field, in which little has been done, but in which an enormous amount can be done in principle. What I want to talk about is the problem of manipulating and controlling things on a small scale. Why cannot we write the entire 24 volumes of the Encyclopedia Britannica on the head of a pin?” said Richard P Feynman in that classic talk he gave on December 29, 1959, at the annual meeting of the American Physical Society at the California Institute of Technology (Caltech). He then emphasised that the title of the talk was ‘There is Plenty of Room at the Bottom’ not just ‘There is Room at the Bottom’.
Pathbreaking technology
Last week marked the 50th anniversary of Feynman’s famous lecture, which many say represents the first introduction to nanotechnology, though Feynman himself never used the word. In 1958, the 41-year-old was one of the leading theoretical physicists in the world, and his work on quantum electrodynamics in the early 1940s would win him a share for the Nobel Prize for Physics in 1965.
Here’s an example of what Feynman said in his talk. “What would our librarian at Caltech say, as she runs all over from one building to another, if I tell her that ten years from now, all of the information that she is struggling to keep track of, 1,20,000 volumes, stacked from the floor to the ceiling, drawers full of cards, storage rooms full of the older books, can be kept on just one library card. When the University of Brazil, for example, finds that their library is burned, we can send them a copy of every book in our library by striking off a copy from the master plate in a few hours and mailing it in an envelope no bigger or heavier than any other ordinary air mail letter.”
Feynman spoke about the need to have better electron microscopes to look at individual atoms distinctly. He also foresaw the need to have miniature computers that could handle enormous amounts of data.
He even suggested we could achieve this using “miniaturisation by evaporation”, wherein you could simply evaporate the appropriate materials, until you have a block of stuff which has the elements, coils, condensers, transistors and so on, of exceedingly fine dimensions.
Twenty five years later, Thomas Newman and Fabian Pease in their lab at Stanford University, used an electron beam to write the first page of Charles Dickens’, A Tale of Two Cities on a silicon nitride surface. They wrote to Feynman on November 11, 1985 to inform him of their accomplishment and collect the prize of $1000. In his reply, Feynman wrote, “You have certainly satisfied my idea of what I wanted to give the prize for.”
Products on offer
Numerous products are already the result of nanotechnology, from cell phone battery boosters to tennis racquets, from indoor air purifiers to self-cleaning glass. In fact, there is not a single industry that eventually won’t be dramatically changed by nanotechnological applications. Nanoscale materials are used in electronic, magnetic and optoelectronic, biomedical, pharmaceutical, cosmetic, energy, catalytic and materials applications.
So far, the greatest revenue generation for nanoparticles is taking place in chemical-mechanical polishing, sunscreens, automotive catalyst supports, biolabeling, electro-conductive coatings and optical fibres, non-volatile magnetic memory, automotive sensors, landmine detectors and solid-state compasses.
The size of computer chips can go only so far before reaching nano-level. Computers based on nanotechnology will have unimaginable storage capacities and operate at nano-speed. Other products already available include step assists on vans, car bumpers, paints and coatings for eyeglasses and cars, metal-cutting tools, sunscreens, cosmetics, stain-free clothing and mattresses among others.
Nanostructured polymers are being used in display technologies for laptops, cell phones and digital cameras. The benefits are brighter images, lighter weight, less power consumption and wider viewing angles.
Another branch of the technology is Nanomedicine, which may be defined as the monitoring, repair, construction and control of human biological systems at the molecular level, using engineered nanodevices and nanostructures.
A sample list of areas covered by and converged with nanomedicine include; biotechnology, genomics, genetic engineering, cell biology, stem cells, cloning, prosthetics, cybernetics, neural medicine, dentistry, cryonics, veterinary medicine, biosensors, biological warfare, cellular re-programming, diagnostics, drug delivery, gene therapy, human enhancement, imaging techniques, skin care and anti-ageing.