The development of quantum dots can be attributed to research from two different laboratories in the early 1980s: Dr. Louis Brus at Bell Laboratories, and Drs. Alexander Efros and A.I. Ekimov of the Yoffe Institute in St. Petersburg (then Leningrad) in the former Soviet Union. Quantum dots are nanosized crystals of semiconductor materials. Originally it was observed that solutions of different sized quantum dots (made of the same material) had different colours. Later, these optical differences were exploited in new applications in for example, medical imaging and lasers.
Carbon nanotubes (CNT) were discovered in 1991 by Sumio Iijima, working at NEC. They are essentially rolled sheets of graphite, and can be single or multi-walled. Depending on the way they are made, they can be conducting or semi-conducting, and therefore have potential applications in electronics. They are also five times less dense than steel and fifty times stronger, and so have applications in composite materials, such as car bumpers. Finally, there are some applications in medicine for drug delivery.
The scanning tunneling microscope (STM) is a non-optical microscope that scans an electrical probe over a surface to be imaged to detect a weak electric current flowing between the tip and the surface. The STM was invented in 1981 by Gerd Binnig and Heinrich Rohrer of IBM's Zurich Lab in Zurich, Switzerland.
The STM allows scientists to visualize regions of high electron density and hence infer the position of individual atoms and molecules on the surface of a lattice.
In 2002, the European Union funded the Nanoforum project to provide a framework for raising awareness, supporting and encouraging the adoption of new nanotechnologies, and facilitating the development of new industrially-oriented nanotechnology research across Europe. Another major activity is the dissemination of information as widely as possible, for example via the media or through special interest groups.
Consumer products making use of nanotechnology started appearing on the market towards the end of the 1990s. These included more aesthetically-pleasing suncreams and cosmetics, sports equipment, car wax, nanosilver wound dressings, and even clothes.
In 1989, IBM scientist Don Eigler was surprised to learn that in addition to using a scanning tunneling microscope (STM) to look at tiny things he could also use it like a pair of tweezers, to move things as small as a single atom.
That year, he used an STM to move individual atoms of the gas xenon that had been cooled to extremely low temperatures so that they sat still, to spell out “IBM” on a nickel surface. He then used the microscope to capture an image of the microscopic logo, and announced his results to the world. This ability to position individual atoms accurately has led to many new discoveries. Eigler’s team, for example, subsequently formed a wall of iron atoms to trap electrons and study how they behave in tightly constrained spaces.
For further information on similar devices, see the Metrology & Standards section.
In the 1980s the basic idea of the nanotechnology definition was explored in much more depth by Dr. Eric Drexler (pictured).
He promoted the technological significance of nano-scale phenomena and devices through speeches and the books Engines of Creation: The Coming Era of Nanotechnology and Nanosystems: Molecular Machinery, Manufacturing, and Computation, and so the term acquired its current sense.
Fullerenes are a recently-discovered form of carbon named after Buckminster Fuller. They can take the form of a hollow sphere, ellipsoid, or tube. Spherical fullerenes are sometimes called buckyballs, the C60 variant is often compared to a typical black and white football. Cylindrical fullerenes are called buckytubes. Fullerenes are similar in structure to graphite, which is composed of a sheet of linked hexagonal rings, but they contain pentagonal (or sometimes heptagonal) rings that prevent the sheet from being planar.
Applications include cosmetics and pharmaceuticals, lubricants for engine parts, and electronics.
The term "nanotechnology" was defined by Tokyo Science University Professor Norio Taniguchi in a 1974 paper as follows: "'Nano-technology' mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or one molecule."
The ancient Romans unknowingly became nanotechnologists when they made red stained glass by mixing gold chloride into molten glass. That created tiny gold spheres (nanoparticles), which absorbed and reflected sunlight in a way that produces a rich ruby color. Colour changes with size, and that is how stained glass windows achieve their brilliance.
Richard Feynman originated the idea of nanotechnology, or molecular machines, in 1959 with his famous lecture 'There's Plenty of Room at the Bottom'.
In it, Feynman challenged scientists to think about constructing atomic scale devices;
a speech that twenty years later encouraged Drexler to publish his early
nanotechnology speculations.
Excerpt of the speech is presented on the right, written with an atomic force microscope by researchers in Chad Mirkin's Laboratory.
Read the full speech here
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This is a brief history of some of the landmarks and pioneers of nanotechnology.
Hover over a timeline object to reveal more!
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