Click for next page ( 2


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 1
Summar`,: THE NATURE OF THE FIELD The goals of atomic, molecular, and optical physics (AMO physics) are to elucidate the fundamental laws of physics, to understand the structure of matter and how matter evolves at the atomic and molecular levels, to understand light in all its manifestations, and to create new techniques and devices. AMO physics provides theoretical and exper- imental methods and essential data to neighboring areas of science such as chemistry, astrophysics, condensed-matter physics, plasma physics, surface science, biology, and medicine. It contributes to the national security system and to the nation's programs in fusion, directed energy, and materials research. Lasers and advanced technol- ogies such as optical processing and laser isotope separation have been made possible by discoveries in AMO physics, and the research underlies new industries such as fiber-optics communications and laser-assisted manufacturing. These developments are expected to help the nation to maintain its industrial competitiveness and its military strength in the years to come. EDUCATIONAL ROLE AMO physics plays an important role in the education of scientists in the United States at both the undergraduate and graduate levels.

OCR for page 1
2 A TOMIC, MOLECULAR, AND OPTICA ~ PHYSICS University-based AMO research prepares students for careers in basic and applied science in industry, in national laboratories, and in universities. Approximately 140 Ph.D. degrees are awarded each year in AMO physics. CONTRIBUTIONS TO NATIONAL PROGRAMS AMO physics contributes broadly to the nation's programs in energy. Experimental and theoretical data from AMO laboratories are needed for fusion research with magnetic or inertial confinement. Spectroscopy and laser scattering are important diagnostic techniques for plasma fusion devices. Inertial-confinement experiments employ charged-particle devices and high-power lasers whose origins lie in AMO research. Using methods from modern optics, the chemistry of combustion can be studied in an engine as it runs, leading to improved efficiency of aircrafts, ships, and automobiles. Basic research in AMO physics has revolutionized important areas of military technology. Atomic clocks and laser gyroscopes are central to modern navigation and global positioning systems; fiber-optics communication is widely used in ships, tanks, and planes. Data on atomic and molecular processes from AMO laboratories are vital to the understanding of atmospheric and meteorological phenomena that affect military scenarios. Lasers are used for range finding, guidance, optical radar, and numerous other applications; high-power lasers are being employed in new classes of countermeasures and directed energy weapons systems. AMO research also contributes broadly to the nation's environmen- tal program. Atomic and molecular data from AMO laboratories are crucial to understanding the chemistry of the atmosphere. Remote- sensing methods employing lasers and laser spectroscopy permit pollutants to be monitored at long distances. Much of our understand- ing of the effect of ionizing radiation on biological systems is based on data and theoretical research from AMO physics. RECENT ADVANCES IN BASIC ATOMIC, MOLECULAR, AND OPTICAL SCIENCE AMO physics encompasses broad areas of theoretical and experi- mental research on matter at the atomic and molecular level and on light. A few of the recent advances in atomic physics include optical spectroscopy of exotic atoms, new tests of quantum electrodynamics through ultraprecise measurements on individual trapped electrons and

OCR for page 1
5 UMMAR Y 3 positrons, the production of very slow, highly charged ions, the prediction and study of spontaneous electron-positron formation in high nuclear fields, and the first direct measurement of dielectronic recombination. In molecular physics the advances include the develop- ment of general techniques for studying molecular ions, the creation of clusters (small groups of isolated molecules), surface scattering with supersonic molecular beams, and the discovery of energy localization in polyatomic molecules. Advances in optics include the first direct measurement of the frequency of an optical transition, the develop- ment of ultraprecise optical spectroscopy and ultrasensitive detection of atoms and molecules, laser cooling of ions and atoms, the coherent generation of far-ultraviolet light, optical bistability, and the creation of numerous new types of lasers and nonlinear optical techniques. These discoveries and numerous theoretical advances, including new ap- proaches made possible by computers, have combined to make the past decade of AMO physics a period of substantial scientific progress and unprecedented productivity. RESEARCH OPPORTUNITIES The field of AMO physics is moving forward rapidly in wide areas of research on the structure and dynamics of atoms and molecules, the control and generation of light, and the fundamental laws of physics. From among the many activities in AMO physics, the Panel has identified a series of topics that hold promise for rapid advance and high scientific reward. These topics form the basis of a Program of Research Initiatives that is described in detail in the report. The initiative in atomic physics includes tests of fundamental physical laws, the development of high-precision techniques, and research on the many-electron problem and on the dynamics of atomic collisions. In molecular physics the research is centered on understanding the motion of electrons and nuclei in molecular fields and the possibility of controlling the exchange of energy and particles during molecular collisions. The initiative in optics includes the development of coherent light sources from the infrared to the x-ray regions, research on new methods of spectroscopy, and quantum optics. This program is intended to advance our knowledge of basic AMO science, assure that the field can continue to provide essential data and new techniques for the other sciences, and allow AMO physics to continue its contributions to vital national programs and industry. The program is needed to provide the research environment that is essential

OCR for page 1
4 A-TOMIC, MOLECULAR, AND OPTICAL PHYSICS for the training of professional scientists for careers in industry, in government laboratories, and in universities. PRIORITIES OF RESEARCH AMO physics in the United States advances most often by the efforts of scientists working in small groups on highly diverse problems. The research is pursued by over 300 of these groups in universities, in national laboratories, and in industrial laboratories. The great strength of AMO physics in the United States is due to the high quality of many of these groups. After a decade of severe winnowing, the remaining groups are seriously threatened by under- funding and the lack of equipment. To assure that the scientific opportunities in AMO physics can be pursued in the United States, the first priority must be to assure the continued vitality of the best of these groups and at the same time to create opportunities for young scientists to enter the field. RECOMMENDATIONS The major recommendations are for primary support for atomic, molecular, and optical research in the Initiative Areas. Eight of these areas have been identified. As explained in the report, a 4-year program is proposed at the end of which a total of approximately 140 groups will be pursuing new research in the Initiative Areas. This number is not large considering the breadth of the areas, the variety of scientific opportunities in each of them, the total size of the field, and the need for a reasonable number of new scientists to enter the field, perhaps one a year in each area. At the end of the 4-year period the field should achieve an equilibrium operating level where new work can be started as old work is phased out. The figures are targets to guide the intensity of the overall effort; they are not meant to fix the exact size of individual grants, the precise number and size of the research groups, or the timetable for starting research in each area. SUPPORT FOR THE RESEARCH INITIATIVES Additional funds are essential for AMO groups to carry forward research under the Program of Research Initiatives. The funds are required to support graduate students, postdoctoral workers, and other professional scientists; to help restore the seriously decayed infrastruc-

OCR for page 1
S UMAlAR Y 5 ture of shops, technicians, and special services; to purchase equipment at an orderly rate and to maintain it; to support travel and visitors and to allow enough flexibility for groups to pursue new scientific leads without the 2- to 3-year delay that is now usually required for starting new research. To undertake the new research, the base level of support for basic AMO physics needs to be incremented by $7 million per year (1984 dollars) each year for the next 4 years. INSTRUMENTATION FOR THE PROGRAM OF RESEARCH INITIATIVES The instrumentation in most AMO laboratories in the United States is now obsolete, and important scientific opportunities are being lost. The situation is becoming grave. New instrumentation must be pro- vided rapidly if the momentum of research is not to be broken. The increase in base support recommended above is intended to let the research groups replace instruments at an orderly rate and to maintain the instruments, but it is not adequate for re-equipping obsolete laboratories. For this purpose special one-time support is essential. To equip AMO laboratories for the pursuit of the initiatives, a special allocation of $11 million (1984 dollars) for instrumentation should be made available each year for the next 4 years. THEORY In contrast to the situation in Europe, Japan, and the Soviet Union, the theoretical atomic community in the United States is small and highly dispersed. There is a critical need to focus the efforts in this country in order to bring the effort up to the level required to guide and interpret the experimental research. The Panel recommends that the agencies invite and support proposals addressing this issue, for exam- ple, by creating centers, workshops, or summer schools where stu- dents and active theorists could come together for varying periods of time. ACCESS TO LARGE COMPUTERS New approaches made possible by large computers are profoundly changing AMO physics, but the lack of computational facilities for theoretical atomic physicists is seriously hindering activity here. On the basis of a survey of potential users, the Panel recommends that over a 4-year period computer time equivalent to one full-time Cray 1

OCR for page 1
6 ATOMIC, MOLECULAR, AND OPTICAL PHYSICS be made available to AMO physicists, supported by high-speed re- mote-access facilities. SPECIAL FACILITIES Accelerator-based atomic physics and research with synchrotron light sources require facilities that are more expensive than those that have been supported in AMO programs in the past. There are compelling scientific opportunities in both of these areas. The Panel recommends that proposals be invited and supported for the creation of high-charge ion sources and for accelerator upgrades, at an estimated total cost of $12 million. The Panel recommends that insertion devices be supported for existing synchrotron light sources and that substantial access to them be made available to the AMO community. The Panel endorses the construction of next-generation light sources, both VUV and x-ray, and recommends that beam lines be provided for the AMO community.