Nanotechnology


What is nanotechnology?


In simple terms, nanotechnology can be defined as ‘engineering at a very small scale’, and this term can be applied to many areas of research and development – from medicine to manufacturing to computing, and even to textiles and cosmetics. Nanotechnology (sometimes shortened to "nanotech") is a multidisciplinary science that studies how we can manipulate matter at the molecular and atomic scale, i.e., is the engineering of tiny machines — the projected ability to build things from the bottom up, using techniques and tools being developed today to make complete, highly advanced products.

Nanotools
Nanotools

Take a random selection of scientists, engineers, investors and the general public and ask them what nanotechnology is and you will receive a range of replies as broad as nanotechnology itself. For many scientists, it is nothing startlingly new; after all we have been working at the nanoscale for decades, through electron microscopy, scanning probe microscopies or simply growing and analyzing thin films. For most other groups, however, nanotechnology means something far more ambitious, miniature submarines in the bloodstream, little cogs and gears made out of atoms, space elevators made of nanotubes, and the colonization of space.

Nanorobot
The robot in this illustration swims through the arteries and veins using a pair of tail appendages.

E-coli
Nanorobot designers sometimes look at microscopic organisms for propulsion inspiration, like the flagellum on this e-coli cell.
 
Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale. It can be difficult to imagine exactly how this greater understanding of the world of atoms and molecules has and will affect the everyday objects we see around us, but some of the areas where nanotechnologies are set to make a difference are described below.



Nanotechnology, in one sense, is the natural continuation of the miniaturization revolution that we have witnessed over the last decade, where millionth of a meter (10-6 m) tolerances (microengineering) became commonplace, for example, in the automotive and aerospace industries enabling the construction of higher quality and safer vehicles and planes.

It was the computer industry who kept on pushing the limits of miniaturization, and many electronic devices we see today have nano features that owe their origins to the computer industry – such as cameras, CD and DVD players, car airbag pressure sensors and inkjet printers.

Nanotechnology is fundamentally a materials science that has the following characteristics:
  • Research and development at molecular or atomic levels, with lengths ranging between about 1 to 100 nanometers;
  • Creation and use of systems, devices, and structures that have special functions or properties because of their small size;
  • Ability to control or manipulate matter on a molecular or atomic scale.

Undoubtedly, nanotechnology is going to be the future, as studies are going on in diversifying the technology from materials with dimensions in nano scale to materials in dimensions of atomic scale. Some new methods like molecular self-assembly have been developed to make this possible. There may be a future when all the common basic needs like food, shelter and even costly diamonds will be made by nanorobots.

Nanorobots
Driller nanorobots (Graphics by Erik Viktor)

What is the nanoscale?


Nanotechnology originates from the Greek word meaning “dwarf”. A nanometre is one billionth of a meter, which is tiny, only the length of ten hydrogen atoms.  Although a meter is defined by the International Standards Organization as "the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second" and a nanometre is by definition 10-9 of a meter, this does not help scientists to communicate the nanoscale to non-scientists.

Although scientists have manipulated matter at the nanoscale for centuries, calling it physics or chemistry, it was not until a new generation of microscopes was invented in the nineteen eighties that the world of atoms and molecules could be visualized and managed. It is in human nature to relate sizes by reference to everyday objects, and the commonest definition of nanotechnology is in relation to the width of a human hair.

Nanoscale
Examples of the nanoscale

In order to understand the unusual world of nanotechnology, we need to get an idea of the units of measure involved. A centimeter is one-hundredth of a meter, a millimeter is one-thousandth of a meter, and a micrometer is one-millionth of a meter, but all of these are still huge compared to the nanoscale.

Rather than asking anyone to imagine a millionth or a billionth of something, which few sane people can accomplish with ease, relating nanotechnology to atoms often makes the nanometre easier to imagine. This clearly shows how small a nano is. It is even smaller than the wavelength of visible light and a hundred-thousandth the width of a human hair. But it is still big when compared to the atomic scale. 
 Nanoscale

Let us compare different units with respect to meters.
  • 1 centimeter – 1,00th of a meter
  • 1 millimeter – 1,000th of a meter
  • 1 micrometer – 1,000,000th of a meter
  • 1 nanometer –  1,000,000,000th of a meter

As small as a nanometer is, it is 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.

Nanoscale

Generally, nanotechnology deals with structures sized between 1 to 100 nanometer in at least one dimension, and involves developing materials or devices within that size. Quantum mechanical effects are very important at this scale, which is in the quantum realm. Larger than that is the microscale, and smaller than that is the atomic scale.

References:
HowStuffWorks
Nanotechnology Now
YouTube

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