Atomic, Molecular, and Optical Science An Investment in the Future (1994) / Chapter Skim
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1 Case Studies in AMO Science
1 Case Studies in AMO Science
Pages 23-35
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From page 23... ...
The case study on carbon nanostructures describes an exciting new area in which potential economic impacts are in the speculative stage. LASERS: FROM BASIC RESEARCH TO NEW TECHNOLOGIES AND NEW INDUSTRIES Lasers, one of the most remarkable products of twentieth-century science and technology, evolved directly from basic AMO research concerning light and its interaction with matter, including atoms, molecules, and solids.
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From page 24... ...
The pinpoint accuracy of "smart" weapons guided to their targets by scattered laser light was graphically demonstrated during Desert Storm. Laser beams may also be focused to extremely small spots, resulting in high energy densities sufficient to melt or vaporize many materials.
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From page 25... ...
Shown here are a conventional helium-neon laser found in a supermarket bar code scanner (top) , a conventional semiconductor diode laser used in a compact-disk player (middle)
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From page 26... ...
The benefits provided by laser technology will continue to increase as new applications are discovered and as new highly reliable, efficient, easy-to-use, and moderately priced devices become available. In this regard, semiconductor diode lasers and solid-state lasers pumped by semiconductor lasers appear particularly attractive because of their modest size and cost and because of the ruggedness of solid-state technology for applications outside a laboratory.
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From page 27... ...
Semiconductor diode laser technology is also rapidly advancing on several fronts. Diode laser arrays are now being developed that provide high average powers and that can be used either alone or as pump sources for solid-state lasers.
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From page 28... ...
What distinguishes this approach from other manipulation techniques is that it permits neutral particles to be positioned and moved without physical contact. The story of optical manipulation illustrates the interplay between basic research and the development of techniques with potential for widespread application in many areas, including ultraprecise atomic clocks, structural engineering at the atomic level (nanotechnology)
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From page 29... ...
Another device that has been made possible by a combination of atom manipulation techniques is the atom interferometer, which takes advantage of the wavelike nature of atomic particles. Conventional optical interferometers are used as extremely sensitive measuring devices, and interferometers based on atoms promise new measurement capabilities and increased precision.
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From page 30... ...
A slight modification of the geometry of the gravity meter may also allow construction of an extremely sensitive atom gyroscope that could greatly increase the accuracy of inertial navigation systems. Optical Tweezers and the Biosciences The work on atom trapping stimulated renewed interest in the manipulation of microscopic neutral particles.
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From page 31... ...
A sample is placed on the stage of a microscope, which has been adapted to admit green laser light and infrared laser radiation. The green light illuminates the sample while the infrared radiation traps and holds it.
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From page 32... ...
To form clusters of refractory elements normally found only as bulk solids, laser ablation methods were developed, and laser spectroscopic methods were devised to characterize their structure. A major fraction of this effort was devoted to clusters of metallic and semiconducting compounds because it was recognized that the strong bonding of these materials might cause the clusters to adopt different, previously unseen, structures and types of bonding.
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From page 33... ...
Simple theoretical considerations and early free radical experiments suggested that small carbon clusters would exist as chains and rings, but there were no reliable predictions of how large a carbon cluster would have to be to exhibit graphite or diamond structure, or what intermediate-sized clusters might actually look like. Carbon, then, was expected to be an intriguing cluster research problem, and in 1985 it was observed quite unexpectedly that a carbon cluster with 60 atoms is far more stable against growth to larger species than are clusters of neighboring numbers of atoms.
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From page 34... ...
Organic molecules can be bonded to the outside of the cage, and this fact allows buckyballs to be incorporated into polymeric "plastics." The possibilities of both outside and inside doping of buckyballs in solids should give electrical properties we cannot now anticipate. The C60 structure, however, is now known to be the smallest member of a family of similar, larger icosahedral structures, the next member of which is C240.
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From page 35... ...
cables that could ever be constructed of any material roughly 100 times stronger than a steel cable of the same diameter and 400 times stronger than steel per unit weight. Nanofibers, doped with metal atoms down the hollow inside cavity, are expected to have electrical conductivity at room temperature substantially higher than pure copper and could provide an attractive replacement for use in electrical power transmission lines worldwide.
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