Computing with nanotechnology: Nanocomputing

Nanocomputer is the logical name for a computer smaller than the microcomputer, which is smaller than the minicomputer. More technically, it is a computer whose fundamental parts are no bigger than a few nanometers.

The world has been moving faster from mini to micro and latest is the nano technology. A nanometer is a unit of measure equal to a billionth of a meter. Ten atoms fit side by side in a nanometer. Nanotechnology today is an emerging set of tools, techniques, and unique applications involving the structure and composition of materials on a nanoscale. Nanotechnology, the art of manipulating materials on an atomic or molecular scale to build microscopic devices such as robots, which in turn will assemble individual atoms and molecules into products much as if they were Lego blocks. Nanotechnology is about building things one atom at a time, about making extraordinary devices with ordinary matter. A nanocomputer is a computer whose physical dimensions are microscopic. The field of nanocomputing is part of the emerging field of nanotechnology. Nanocomputing describes computing that uses extremely small, or nanoscale, devices (one nanometer [nm] is one billionth of a meter).
A nanocomputer is similar in many respects to the modern personal computer, but on a scale that's very much smaller. With access to several thousand (or millions) of nanocomputers, depending on users needs or requirements gives a whole new meaning to the expression "unlimited computing" users may be able to gain a lot more power for less money. Several types of nanocomputers have been suggested or proposed by researchers and futurists. Electronic nanocomputers would operate in a manner similar to the way present-day microcomputers work. The main difference is one of physical scale. More and more transistors are squeezed into silicon chips with each passing year; witness the evolution of integrated circuits (IC s) capable of ever-increasing storage capacity and processing power. The ultimate limit to the number of transistors per unit volume is imposed by the atomic structure of matter. Most engineers agree that technology has not yet come close to pushing this limit. In the electronic sense, the term nanocomputer is relative. By 1970s standards, today's ordinary microprocessors might be called nanodevices.
Chemical and biochemical nanocomputers have the power to store and process information in terms of chemical structures and interactions. Biochemical nanocomputers already exist in nature; they are manifest in all living things. But these systems are largely uncontrollable by humans. The development of a true chemical nanocomputer will likely proceed along lines similar to genetic engineering. Engineers must figure out how to get individual atoms and molecules to perform controllable calculations and data storage tasks.
Mechanical nanocomputers would use tiny moving components called nanogears to encode information. Such a machine is suggestive of Charles Babbage’s analytical engines of the 19th century. For this reason, mechanical nanocomputer technology has sparked controversy; some researchers consider it unworkable. All the problems inherent in Babbage's apparatus, according to the naysayers, are magnified a millionfold in a mechanical nanocomputer. Nevertheless, some futurists are optimistic about the technology, and have even proposed the evolution of nanorobots that could operate, or be controlled by, mechanical nanocomputers.
A quantum nanocomputer would work by storing data in the form of atomic quantum states or spin. Technology of this kind is already under development in the form of single-electron memory (SEM) and quantum dots. The energy state of an electron within an atom, represented by the electron energy level or shell, can theoretically represent one, two, four, eight, or even 16 bits of data. The main problem with this technology is instability. Instantaneous electron energy states are difficult to predict and even more difficult to control. An electron can easily fall to a lower energy state, emitting a photon; conversely, a photon striking an atom can cause one of its electrons to jump to a higher energy state.
There are several ways nanocomputers might be built, using mechanical, electronic, biochemical, or quantum technology. It is unlikely that nanocomputers will be made out of semiconductor transistors (Microelectronic components that are at the core of all modern electronic devices), as they seem to perform significantly less well when shrunk to sizes under 100 nanometers.
Computing systems implemented with nanotechnology will need to employ defect- and fault-tolerant measures to improve their reliability due to the large number of factors that may lead to imperfect device fabrication as well as the increased susceptibility to environmentally induced faults when using nanometer-scale devices. Researchers have approached this problem of reliability from many angles and this survey will discuss many promising examples, ranging from classical fault-tolerant techniques to approaches specific to nanocomputing. The research results summarized here also suggest that many useful, yet strikingly different solutions may exist for tolerating defects and faults within nanocomputing systems. Also included in the survey are a number of software tools useful for quantifying the reliability of nanocomputing systems in the presence of defects and faults.
The potential for a microscopic computer appears to be endless. Along with use in the treatment of many physical and emotional ailments, the nanocomputer is sometimes envisioned to allow for the ultimate in a portable device that can be used to access the Internet, prepare documents, research various topics, and handle mundane tasks such as email. In short, all the functions that are currently achieved with desktop computers, laptops, and hand held devices would be possible with a nanocomputer that is inserted into the body and directly interacts with the brain.
Despite the hype about nanotechnology in general and nanocomputing in particular, a number of significant barriers must be overcome before any progress can be claimed.
Work is needed in all areas associated with computer hardware and software design:
• Nanoarchitectures and infrastructure
• Communications protocols between multiple nanocomputers, networks, grids, and the Internet
• Data storage, retrieval, and access methods
• Operating systems and control mechanisms
• Application software and packages
• Security, privacy, and accuracy of data
• Circuit faults and failure management
Basically, the obstacles can be divided into two distinct areas:
Hardware: the physical composition of a nanocomputer, its architecture, its communications structure, and all the associated peripherals
Software: new software, operating systems, and utilities must be written and developed, enabling very small computers to execute in the normal environment.

Nanocomputers have the potential to revolutionize the 21st century. Increased investments in nanotechnology could lead to breakthroughs such as molecular computers. Billions of very small and very fast (but cheap) computers networked together can fundamentally change the face of modern IT computing in corporations that today are using mighty mainframes and servers. This miniaturization will also spawn a whole series of consumer-based computing products: computer clothes, smart furniture, and access to the Internet that's a thousand times faster than today's fastest technology.
Nanocomputing's best bet for success today comes from being integrated into existing products, PCs, storage, and networks—and that's exactly what's taking place.
The following list presents just a few of the potential applications of nanotechnology:
• Expansion of mass-storage electronics to huge multi-terabit memory capacity, increasing by a thousand fold the memory storage per unit. Recently, IBM's research scientists announced a technique for transforming iron and a dash of platinum into the magnetic equivalent of gold: a nanoparticle that can hold a magnetic charge for as long as 10 years. This breakthrough could radically transform the computer disk-drive industry.
• Making materials and products from the bottom up; that is, by building them from individual atoms and molecules. Bottom-up manufacturing should require fewer materials and pollute less.
• Developing materials that are 10 times stronger than steel, but a fraction of the weight, for making all kinds of land, sea, air, and space vehicles lighter and more fuel-efficient. Such nanomaterials are already being produced and integrated into products today.
• Improving the computing speed and efficiency of transistors and memory chips by factors of millions, making today's chips seem as slow as the dinosaur. Nanocomputers will eventually be very cheap and widespread. Supercomputers will be about the size of a sugar cube.