Nano Technology
Nanotechnology (sometimes shortened to "nanotech") is the manipulation of matter on an atomic and molecular scale. The earliest, widespread description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macro scale products, also now referred to as molecular nanotechnology .
A more generalized description of nanotechnology was subsequently established by the National Nanotechnology Initiative, which defines nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nano meters.
This definition reflects the fact that quantum mechanical effects are important at this quantum-realm scale, and so the definition shifted from a particular technological goal to a research category inclusive of all types of research and technologies that deal with the special properties of matter that occur below the given size threshold. It is therefore common to see the plural form "nanotechnologies" as well as "nano-scale technologies" to refer to the broad range of research and applications whose common trait is size.
Current Research :
Nano materials
Bottom-up approaches
Top-down approaches
Functional approaches
Biomimetic approaches
Speculative
Nanomaterials is a field that takes a materials science-based approach on nanotechnology. It studies materials with morphological features on the nanoscale, and especially those that have special properties stemming from their nanoscale dimensions. Nanoscale is usually defined as smaller than a one tenth of a micrometer in at least one dimension, though sometimes includes up to a micrometer.
Bottom–Up Approach:
Bottom-up, or self-assembly, approaches to nano-fabrication use chemical or physical forces operating at the nano-scale to assemble basic units into larger structures. As component size decreases in nano-fabrication, bottom-up approaches provide an increasingly important complement to top-down techniques. Inspiration for bottom-up approaches comes from biological systems, where nature has harnessed chemical forces to create essentially all the structures needed by life. Researchers hope to replicate nature’s ability to produce small clusters of specific atoms, which can then self-assemble into more-elaborate structures.
Top-Down Approach:
The most common top-down approach to fabrication involves lithographic patterning techniques using short-wavelength optical sources. A key advantage of the top-down approach—as developed in the fabrication of integrated circuits—is that the parts are both patterned and built in place, so that no assembly step is needed. The top–down approach combines both conventional and unconventional methods to generate and replicate nano-scale structures in a fashion similar to “carving” smaller objects from a large bulk material.
Biomimetic Approaches:
This fruitful collaboration between materials science, biology and biomedicine for the advancement of biomaterials collects the most promising solutions provided by nature for the field of biomedicine, showing how to achieve the desired functionality by using biomimetic. It consist of :-
Bionics or biomimicry: having normal biological capability or performance enhanced by or as if by electronic or electromechanical devices
Bionanotechnology: are terms that refer to the intersection of nanotechnology and biology.
Functional approaches:
These seek to develop components of a desired functionality without regard to how they might be assembled.
Molecular scale electronics seeks to develop molecules with useful electronic properties. These could then be used as single-molecule components in a nano-electronic device. For an example see rotaxane.
Synthetic chemical methods can also be used to create synthetic molecular motors, such as in a so-called nano-car.
Speculative:
These sub fields seek to anticipate what inventions nanotechnology might yield, or attempt to propose an agenda along which inquiry might progress. These often take a big-picture view of nanotechnology, with more emphasis on its societal implications than the details of how such inventions could actually be created.
