Nanotechnology

Nanotechnology is science at the size of individual atoms and molecules: objects and devices measuring mere billionths of a meter, smaller than a red blood cell. Nanotechnology is rapidly becoming an interdisciplinary field. Biologists, chemists, physicists and engineers are all involved in the study of substances at the nanoscale.

Nanoscale

Experts sometimes disagree about what constitutes the nanoscale, but in general, you can think of nanotechnology dealing with anything measuring between 1 and 100 nm. Larger than that is the microscale, and smaller than that is the atomic scale.

As small as a nanometer is, it's still large compared to the atomic scale. An atom has a diameter of about 0.1 nm. An atom's nucleus is much smaller -- about 0.00001 nm. Atoms are the building blocks for all matter in our universe. You and everything around you are made of atoms. Nature has perfected the science of manufacturing matter molecularly. For instance, our bodies are assembled in a specific manner from millions of living cells. Cells are nature's nanomachines.

At the atomic scale, elements are at their most basic level. On the nanoscale, we can potentially put these atoms together to make almost anything. In a lecture called "Small Wonders: The World of Nanoscience," Nobel Prize winner Dr. Horst Störmer said that the nanoscale is more interesting than the atomic scale because the nanoscale is the first point where we can assemble something -- it's not until we start putting atoms together that we can make anything useful.

One of the exciting and challenging aspects of the nanoscale is the role that quantum mechanics plays in it. At nanoscale, materials have different chemical and physical properties than those of the same materials in bulk, because quantum mechanics is more important. The rules of quantum mechanics are very different from classical physics, ­which means that the behavior of substances at the nanoscale can sometimes contradict common sense by behaving erratically.

For example, carbon atoms can conduct electricity and are stronger than steel when woven into hollow microscopic threads. You can't walk up to a wall and immediately teleport to the other side of it, but at the nanoscale an electron can -- it's called electron tunneling. Substances that are insulators in bulk form, meaning that they can't carry an electric charge,  might become semiconductors when reduced to the nanoscale. Melting points can change due to an increase in surface area. Much of nanoscience requires that you forget what you know and start learning all over again.

So what does this all mean? Right now, it means that scientists are experimenting with substances at the nanoscale to learn about their properties and how we might be able to take advantage of them in various applications. Engineers are trying to use nano-size wires to create smaller, more powerful microprocessors. Doctors are searching for ways to use nanoparticles in medical applications. Still, we've got a long way to go before nanotechnology dominates the technology and medical markets.

At this time, nanoparticles are already widely used in certain commercial consumer products, such as suntan lotions, "age-defying" make-up, and self-cleaning windows that shed dirt when it rains. One company manufactures a nanocrystal wound dressing with built-in antibiotic and anti-inflammatory properties.

On the horizon is toothpaste that coats, protects and repairs damaged enamel, as well as self-cleaning shoes that never need polishing. Nanoparticles are also used as additives in building materials to strengthen the walls of any given structure, and to create tough, durable, yet lightweight fabrics.

Reference Books: Nanotechnology

Nano-Optoelectronics	Foundations of Nanomechanics by Andrew N. Cleland	Nanostructuring Operations in Nanoscale Science and Engineering by Kal Sharma	Nano-Optics by James Hsu	Foundations of Nanomechanics