U.S.-Austria Cooperative Research: Multiphoton Excitation of Complex Atoms (Physics)

美国-奥地利合作研究：复杂原子的多光子激发（物理学）

• 批准号: 8619833
• 负责人: Walter Johnson
• 金额: $ 0.57万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-15 至 1990-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8619833&HistoricalAwards=false
• 关键词: U.S.; Austria; Cooperative; Research; Multiphoton

This award will support a three-year cooperative research project in physics between Professor Walter R. Johnson, Department of Physics, University of Notre Dame, and Dr. Peter Zoller, Institute for Theoretical Physics, University of Innsbruck, Austria. The scientists and members of their research groups are collaborating in theoretical calculations regarding multiphoton ionization of atoms. The goal is to develop a modern theoretical basis for the description of this process, particularly in heavy atoms, including the effects of electron-electron correlation. The theoretical framework of the calculations will be the time-dependent Hartree-Fock method. Parallel to this work, a quantum defect theory of nonlinear optical processes will be developed. Current interest in multiphoton processes stems in large part from the availability of lasers. When certain atoms are subjected to high intensities of laser radiation, there is an unexpected, enhanced production of multiply charged ions. It is to explain such experimental results on a quantitative basis that both research groups wish to develop a modern theory of multiphoton ionization. At the present time, theoretical analyses of multiphoton ionization processes in atoms are usually based on the so-called independent particle model of the atom, which neglects interactions between the electrons (electron correlation effects). This model is simple, but does not give satisfactory results when applied to atoms with several electrons in the outer shells, such as the alkaline earth and rare gas atoms. Professor Johnson has developed methods for treating such atoms that go beyond the independent particle model. His expertise in electron correlation effects in atoms will be combined with that of Dr. Zoller, whose field of research is laser-atom interactions and multiphoton processes. Funds from this award would support necessary transportation and subsistence expenses for the U.S. principal investigator and a member of his research group. The Austrian Science Foundation (FWF) is providing counterpart support for the project and has approved the inclusion of this activity under the Memorandum of Understanding between the NSF and the FWF.

该奖项将支持一个为期三年的合作研究项目， 物理学教授沃尔特·R。约翰逊，物理系， 圣母大学和研究所的Peter Zoller博士 奥地利因斯布鲁克大学理论物理学。 科学家 他们的研究小组成员正在合作进行理论研究， 关于原子的多光子电离的计算。 目标是 发展一个现代的理论基础来描述这个过程， 特别是在重原子中，包括电子-电子效应 相关性 计算的理论框架将是 含时Hartree-Fock方法 与此同时，一个量子 将发展非线性光学过程的缺陷理论。 目前对多光子过程的兴趣在很大程度上源于 激光器的可用性。 当某些原子受到高温 激光辐射的强度，有一个意想不到的，增强 产生多电荷离子。 这是为了解释这样的实验 两个研究小组都希望在定量的基础上得出结果， 发展出一套现代的多光子电离理论。 目前， 对原子多光子电离过程进行了理论分析， 通常基于所谓的原子独立粒子模型， 其忽略了电子之间的相互作用（电子相关性 效果）。 这个模型虽然简单，但并没有给出令人满意的结果 当应用于外层有几个电子的原子时， 如碱土金属和稀有气体原子。 约翰逊教授 开发出了处理这些原子的方法， 粒子模型 他在原子电子相关效应方面的专长 将与佐勒博士的研究相结合，佐勒博士的研究领域是 激光-原子相互作用和多光子过程。 资金来源于此 赔偿金将用于支付必要的交通和生活费用 美国首席研究员和他的研究小组的一名成员。 奥地利科学基金会（FWF）正在提供对应支助 并已批准将这一活动列入 NSF和FWF之间的谅解备忘录。