Please note! This essay has been submitted by a student.
Nanotechnology is the name given to a specific sort of manufacturing technology to build things from the atom level, and to rearrange matter with atomic precision. In other words, we can say that nanotechnology is a three dimensional structural control of material and devices at molecular level. The nano scale structures can be prepared, characterized, manipulated, and even visualized with tools.
So, we can say Nanotechnology is a tool-driven field.
Other terms, such as molecular engineering manufacturing are also often applied while describing this emerging technology. This technology does not yet exist. But, scientists have recently gained the ability to observe and manipulate atoms directly. However, this is only one small aspect of a growing array of techniques in nano scale science and technology.
Nano-Technology is Engineering, not Science.
Nanotechnology is often called the science of the small. It is concerned with manipulating particles at the atomic level, usually in order to form new compounds or make changes to existing substances. Nanotechnology is being applied to problems in electronics, biology, genetics and a wide range of business applications.
The central thesis of nanotechnology is that almost any chemically stable structure that is not specifically disallowed by the laws of physics can in fact be built. Theoretical and computational models indicate that molecular manufacturing systems are possible and they do not violate existing physical law.
Matter is composed of small atoms that are closely bound together, making up the molecular structure, which, in turn determines the density of the concerned material. Since different factors such as molecular density, malleability, ductility and surface tension come into play, nano systems have to be designed in a cost effective manner that overrides these conditions and helps to create machines capable of withstanding the vagaries of the environment.
History of Nano-Technology
In 1986-five years after IBM researchers invented the scanning tunnelling microscope that created a sensation for its depiction of godlike control over matter. A book written by K. Eric Drexler describes self-replicating nano machines that could produce virtually any material, while reversing global warming, curing diseases and dramatically extending life spans. Scientists with tenured faculty positions and NSF grants ridiculed these visions, noting that their fundamental improbability made them an absurd projection of what the future holds.
But the visionary scent that has surrounded nanotechnology ever since may provide some unforeseen benefits. To many non-scientists, Drexler’s projections for nanotechnology straddled the border between science and fiction in a compelling way. Talk of cell-repair machines that would eliminate aging as we know it and of home food-growing machines that could produce victuals without killing anything helped to create a fascination with the small that genuine scientists, consciously or not, would later use to draw attention to their work on more mundane but eminently more real projects. Certainly labelling a research proposal ‘nanotechnology’ has a more alluring ring than calling it ‘applied mesoscale materials science.’
Less directly, Drexler’s work may actually draw people into science. His imaginations have inspired a rich vein of science-fiction literature. As a subgenre of science fiction-rather than a literal prediction of the future-books about Drexlerian nanotechnology may serve the same function as Star Trek does in stimulating a teenager’s interest in space, a passion that sometimes leads to a career in aeronautics or astrophysics.
The danger comes when intelligent people take Drexler’s predictions at face value. Drexlerian nanotechnology drew renewed publicity last year when a morose Bill Joy, the chief scientist of Sun Microsystems, worried in the magazine Wired about the implications of nano robots that could multiply uncontrollably. A spreading mass of self-replicating robots-what Drexler has labelled ‘Gray goo’-could pose enough of a threat to society, he mused, that we should consider stopping development of nanotechnology. But that suggestion diverts attention from the real nano goo: chemical and biological weapons.
What would it mean if we could inexpensively make things with every atom in the right place? For starters, we could continue the revolution in computer hardware right down to molecular gates and wires –something that today’s lithographic methods (used to make computer chips) could never hope to do. We could inexpensively make very strong and very light materials: shatterproof diamond in precisely the shapes we want, by the ton, and over fifty times lighter than steel of the same strength. We could make a Cadillac that weighed fifty kilograms, or a full-sized sofa you could pick up with one hand. We could make surgical instruments of such precision and deftness that they could operate on the cells and even molecules from which we are made –something well beyond today’s medical technology. The list goes on –almost any manufactured product could be improved, often by orders of magnitude.
Quantum Uncertainty Principle
An early concern regarding the feasibility of nanotechnology involved quantum uncertainty: would it make these systems unreliable? Quantum uncertainty says that particles must be described as small smears of probability, not as points with perfectly defined locations. This is, in fact, why the atoms and molecules in the simulations felt so soft and smooth. Their electrons are smeared out over the whole volume of the molecule, and these electron clouds taper off smoothly and softly toward the edges. Atoms themselves are a bit uncertain in position, but this is a small effect compared to thermal vibrations. Initially, it will be possible to build Nano machines and molecular-manufacturing systems that work a particular sort of environment, say, an electric or magnetic field (biological mechanisms are an existence proof), but in the long run, there will be no need to do so. Nano machines can be built from the more stable sorts of structure. This has been demonstrated by control of molecular electric dipoles, nano switches, nanowires and devices like Scanning Tunnelling Microscope. Molecular nanotechnology falls entirely within the realm of the possible.
Scope of Nanotechnology
Today, most airplanes are made of metal despite the fact that diamond has a strength-to-weight ratio over 50 times that of aerospace aluminium. Diamond is expensive, we can’t make it in the shapes we want, and it shatters. Nanotechnology will let us inexpensively make shatterproof diamond (with a structure that might resemble diamond fibres) in exactly the shapes we want. This would let us make a Boeing 747 whose unloaded weight was 50 times lighter but just as strong.
Today, computer chips are made using lithography (stone writing). If the computer hardware revolution is to continue at its current pace, in a decade or so we’ll have to move beyond lithography to some new post lithographic manufacturing technology. Ultimately, each logic element will be made from just a few atoms.
Designs for computer gates with less than 1,000 atoms have already been proposed –but each atom in such a small device has to be in exactly the right place. To economically build and interconnect trillions upon trillions of such small and precise devices in a complex three-dimensional pattern we’ll need a manufacturing technology well beyond today’s lithography: we’ll need nanotechnology.
Molecular electronics is a revolutionary idea to attend maximum miniaturization, instead of using transistor’s ‘ON’ and ‘OFF’ states for implementing ones and zeros respectively, the characteristics of electrons maybe used for the same. Positive and negative spins can be used to implement one and zero respectively. The idea is new and it will take time for its implementation but this will be the ultimate destination in the quest for miniaturization.
It is not modern medicine that does the healing, but the cells themselves. If we had surgical tools that were molecular both in their size and precision, we could develop a medical technology that for the first time would let us directly heal the injuries at the molecular and cellular level that are the root causes of disease and ill health. With the precision of drugs combined with the intelligent guidance of the surgeon’s blades, we can expect a quantum leap in our medical capabilities.
A ROLE FOR ENGINEERING
Physical, chemical, biological, materials and engineering sciences have arrived to nanoscale about the same time. Engineering plays an important role because when we refer to nanotechnology we speak about ‘systems’ at nanoscale, where the treatment of simultaneous phenomena in multibody assemblies would require integration of disciplinary methods of investigation and an engineering system approach. The manipulation of a large system of molecules is equally challenging to a thermodynamics engineer researcher as it is to a single-electron physics researcher. They need to work together. Engineering needs to redefine its domain of relevance to effectively take this role in conjunction with other disciplines.
Advantages of Nanotechnology
• Suitable for low cost, high-volume production
• Reduced size, mass and power consumption
• High functionality
• Improved reliability and robustness
Nanotechnology has nothing to do with nuclear technology. There is no transmuting of nuclei as the alchemists tried to do, and as is done by nuclear technologists. Nanotechnology only does what chemists do: rearrange molecules. Nonetheless, it is a technology where the principle of exponentiation can be brought to bear: nuclear explosions come from an exponential proliferation of neutrons in acritical mass of fissile material. Here, we are talking not about an exponential growth of destroying things and releasing energy, but we are talking about a potential exponential growth of constructing complex artefacts.
The work in nanotechnology is being carried out not just on the materials of the future, but also the tools that will allow us to use these ingredients to create products. Experimental work has already resulted in the production of scanning tunnelling microscope, molecular tweezers, and logic devices. Theoretical work in the construction of nano-computers is progressing as well. Taking all of this into account, it is clear that the technology is feasible. Nanotechnology is expected to have a profound impact on our economy and society in the 21st century, from the development of better, faster, stronger, smaller, and cheaper systems. Nanotechnology provides a far more powerful capability. We cannot make powerful computers, defence, environment and medicine, but also in a higher standard of living for everyone on the planet.