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Welcome to the nanotechnology portal

Nanotechnology is the study of manipulating matter on an atomic and molecular scale. Generally, nanotechnology deals with developing materials, devices, or other structures possessing at least one dimension sized from 1 to 100 nanometers.

Nanotechnology is very diverse, including extensions of conventional device physics, new approaches based on molecular self-assembly, developing new materials with nanoscale dimensions, and investigating whether we can directly control matter on the atomic scale. Nanotechnology entails the application of fields as diverse as surface science, organic chemistry, molecular biology, semiconductor physics, microfabrication, etc.

There is much debate on the future implications of nanotechnology. Nanotechnology may be able to create many new materials and devices with a vast range of applications, such as in medicine, electronics, biomaterials and energy production. On the other hand, nanotechnology raises many of the same issues as any new technology, including concerns about the toxicity and environmental impact of nanomaterials, and their potential effects on global economics, as well as speculation about various doomsday scenarios.


A putative molecular planetary gear system

High-resolution transmission electron microscopy

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High-resolution transmission electron microscopy (HRTEM) is an imaging mode of the transmission electron microscope that allows for direct imaging of the atomic structure of the sample. HRTEM is a powerful tool to study properties of materials on the atomic scale, such as semiconductors, metals, nanoparticles and sp2-bonded carbon (e.g. graphene, C nanotubes). At present, the highest point resolution realised in phase contrast TEM is around 0.5 ångströms (0.050 nm). At these small scales, individual atoms of a crystal and its defects can be resolved. For 3-dimensional crystals, it may be necessary to combine several views, taken from different angles, into a 3D map. This technique is called electron crystallography.

One of the difficulties with HRTEM is that image formation relies on phase contrast. In phase-contrast imaging, contrast is not necessarily intuitively interpretable, as the image is influenced by aberrations of the imaging lenses in the microscope. The largest contributions for uncorrected instruments typically come from defocus and astigmatism. The latter can be estimated from the so-called Thon ring pattern appearing in the Fourier transform modulus of an image of a thin amorphous film.


Optical properties of carbon nanotubes

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A photoluminescence map from single-wall carbon nanotubes. (n, m) indexes identify certain semiconducting nanotubes.
Credit: User:NIMSoffice on Commons

A photoluminescence map from single-wall carbon nanotubes


James Gimzewski

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James Kazimierz Gimzewski is a Scottish physicist who pioneered research on electrical contacts with single atoms and molecules, and light emission using scanning tunneling microscopy. Until February 2001, he was a group leader at the IBM Zurich Research Laboratory, and is now a professor of chemistry and biochemistry at the University of California, Los Angeles. He shared a 1997 Feynman Prize in Nanotechnology "for work using scanning probe microscopes to manipulate molecules".



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