The classic speech from Feynman from 1959 in which he said that the basic principles of the physics do not contradict the ability of moving atoms and molecules is often seen as starting point of nanotechnology.
Feynman described a process by which the ability to manipulate individual atoms and molecules might be developed, using one set of precise tools to build and operate another proportionally smaller set, so on down to the needed scale.
Nanotechnology and nanoscience got started in the early 1980s with two major developments; the birth of cluster science and the invention of the scanning tunneling microscope (STM).
The STM is based on the concept of quantum tunneling. When a conducting tip is brought very near to the surface to be examined, a bias (voltage difference) applied between the two can allow electrons to tunnel through the vacuum between them. The resulting tunneling current is a function of tip position, applied voltage, and the local density of states (LDOS) of the sample. Information is acquired by monitoring the current as the tip's position scans across the surface, and is usually displayed in image form.
The resolution of an image is limited by the radius of curvature of the scanning tip of the STM. Additionally, image artifacts can occur if the tip has two tips at the end rather than a single atom; this leads to “double-tip imaging,” a situation in which both tips contribute to the tunneling.
Schematic view of an STM
Cluster science emerged as a separate direction of research in the 1980s, although first reports of cluster species date back already to the 1940s One purpose of the research was to study the gradual development of collective phenomena which characterize a bulk solid. These are for example the color of a body, its electrical conductivity, its ability to absorb or reflect light, and magnetic phenomena such as Ferro-, Ferri-, or anti ferromagnetism. These are typical collective phenomena which only develop in an aggregate of a large number of atoms.
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