Strong Field and Ultrafast Atomic and Molecular Processes

强场和超快原子和分子过程

• 批准号: 1208059
• 负责人: Anthony Starace
• 金额: $ 27万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1208059&HistoricalAwards=false
• 关键词: Strong; Field; Ultrafast; Atomic; Molecular

Intellectual Merit: This project focuses on understanding theoretically the interaction of intense coherent laser radiation with electrons, atoms, and molecules and on investigating the use of ultrashort (attosecond scale) laser or electron pulses to image the time-dependent motion of electrons in atoms and molecules. The interactions of electrons with both intense laser fields and with atomic and molecular potentials are difficult to describe accurately; also, their interactions with ultrashort laser or electron pulses must be described time-dependently. We have developed a number of theoretical approaches to overcome these difficulties. In particular, we have solved essentially exactly the problem of a weakly bound electron in a short-range potential interacting with an intense laser field and the results obtained for this particular system can be accurately generalized to the case of other, more complex atomic and molecular systems. Our investigations include: (1) using short (attosecond scale) electron pulses as both temporal and spatial probes of electron motion in both atoms and molecules; (2) investigating the utility of using intense lasers to assist or induce electron scattering from atoms, electron recombination with atoms, and electron bremsstrahlung (radiative) processes in the vicinity of atoms; (3) developing analytic formulas for laser-induced high-order harmonic generation for the heretofore analytically unexplored cases of elliptically-polarized laser fields, crossed two-color laser fields, and chirped, few-cycle laser fields, both for atoms and for asymmetric diatomic molecules. Broader Impacts: Graduate students and postdoctoral researchers involved with this project are given a broad education in theoretical atomic physics, first hand experience in all aspects of scientific communication, and in teaching undergraduates at a large Big 10 Land Grant university. Project results are not only published in leading physics journals and presented at national and international meetings, but are also periodically distilled and integrated with related work by others in review articles written by the PI and collaborators. All graduate students and postdoctoral researchers involved with this project in the past have been sought after by a variety of other employers, including technology companies, medical researchers, and other leading AMO theory groups. The basic research supported by this project contributes broadly to our understanding of means to control matter on an atomic scale. Our work on increasing the intensities of high order harmonics may one day lead to sources of coherent x-rays, thus providing a new means for visualizing living biological structures as well as nanoscale material structures. Our investigations involving ultrashort (attosecond) pulses of electrons may lead to ways of resolving electron motion both temporally and spatially. The P.I.'s membership on the American Physical Society's Publications Oversight Committee (2010-2013) and on the Science Advisory Board of the Max Planck Institute on the Physics of Complex Systems (2007-2013), a major theoretical atomic physics center in Dresden, Germany, is evidence of his continuing service to the scientific community.

智力优势：该项目的重点是从理论上理解强相干激光辐射与电子，原子和分子的相互作用，并研究使用超短（阿秒尺度）激光或电子脉冲来成像原子和分子中电子随时间的运动。 电子与强激光场以及原子和分子势的相互作用很难精确描述;而且，它们与超短激光或电子脉冲的相互作用必须依赖于时间来描述。我们已经开发了一些理论方法来克服这些困难。特别是，我们已经基本上完全解决了一个弱束缚电子在一个强激光场相互作用的短距离潜力的问题，并为这个特定的系统所获得的结果可以准确地推广到其他的情况下，更复杂的原子和分子系统。我们的调查包括：（1）使用短（2）研究强激光辅助或诱导电子从原子散射、电子与原子复合以及电子韧致辐射的实用性原子附近的（辐射）过程;（3）对于椭圆-椭圆-椭圆的情况，建立了激光诱导高次谐波产生的解析公式。偏振激光场、交叉双色激光场和啁啾的少周期激光场，对于原子和不对称双原子分子都是如此。更广泛的影响：参与该项目的研究生和博士后研究人员在理论原子物理学方面获得了广泛的教育，在科学传播的各个方面获得了第一手经验，并在一所大型的十大赠地大学教授本科生。 项目成果不仅发表在领先的物理学期刊上，并在国家和国际会议上发表，而且还定期在PI和合作者撰写的评论文章中与其他人的相关工作进行提炼和整合。 过去参与该项目的所有研究生和博士后研究人员都受到了各种其他雇主的追捧，包括技术公司，医学研究人员和其他领先的AMO理论团体。该项目支持的基础研究广泛地有助于我们理解在原子尺度上控制物质的方法。 我们在提高高次谐波强度方面的工作可能有一天会导致相干X射线源，从而为可视化活体生物结构以及纳米级材料结构提供新的手段。我们的调查涉及超短（阿秒）脉冲的电子可能会导致解决电子运动的时间和空间的方式。私家侦探他是美国物理学会出版物监督委员会成员（2010-2013年）和马克斯·普朗克复杂系统物理研究所科学顾问委员会成员（2007-2013年），该研究所是德国德累斯顿的一个主要理论原子物理中心，这证明了他对科学界的持续服务。