RUI: Classical and Quantum Studies of Non-Sequential Multiple Ionization of Atoms in Strong Laser Fields

RUI：强激光场中原子非顺序多次电离的经典和量子研究

• 批准号: 0969984
• 负责人: Stanley Haan
• 金额: $ 17.96万
• 依托单位: Calvin University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0969984&HistoricalAwards=false
• 关键词: RUI; Classical; Quantum; Studies; Non

Desktop computers are employed to model the double ionization of atoms by high-intensity visible or infrared laser light. Of particular interest is the process of "non-sequential double ionization", in which two electrons share the energy from a large number of laser photons and escape an atom. The dominant mechanism for this process is now accepted to be recollision, a process in which one electron moves outward from the atom, absorbs energy from the laser, then returns and shares energy with the other electron. Many parts of this process are turning out to be describable using classical physics rather than quantum mechanics, and a significant component of the project involves investigating the limitations of classical analysis. In addition, the final momenta of the doubly ionized electron pairs and possible correlations between these momenta are investigated. Chaotic behavior in the classical system is investigated, as well as the importance of laser intensity, frequency, and pulse shape in the ionization process. Recollision lies at the heart of the growing field of "attosecond science", and the present work helps to provide a solid foundation for that growing area.Impacts of this project emerge from scientific knowledge that is gained, from computer techniques that are developed and from educational components. Many systems, particularly molecular ones, are too complicated for full quantum analysis, but may be amenable to classical analysis. The knowledge gained in the present study regarding the limitations of classical analysis should prove useful in these other areas. The computer techniques being developed in this project are adaptable into other areas and will be useful to other researchers in coming years. In addition, and very importantly, the project features extensive involvement by undergraduate physics students. They benefit not only through increased knowledge of the field and improved computer skills, but also through the development of thinking skills and intellectual habits.

使用台式计算机来模拟高强度可见光或红外激光下原子的双电离。 特别令人感兴趣的是“非顺序双电离”过程，其中两个电子共享大量激光光子的能量并逃离原子。 现在，这一过程的主要机制被认为是重碰撞，在这一过程中，一个电子从原子中向外移动，吸收来自激光的能量，然后返回并与另一个电子共享能量。 这个过程的许多部分都可以使用经典物理学而不是量子力学来描述，并且该项目的一个重要组成部分涉及研究经典分析的局限性。 此外，还研究了双电离电子对的最终动量以及这些动量之间可能的相关性。 研究了经典系统中的混沌行为，以及电离过程中激光强度、频率和脉冲形状的重要性。 重碰撞是“阿秒科学”不断发展的领域的核心，目前的工作有助于为该不断发展的领域提供坚实的基础。该项目的影响来自于所获得的科学知识、开发的计算机技术和教育内容。 许多系统，特别是分子系统，对于完整的量子分析来说过于复杂，但可能适合经典分析。 在本研究中获得的有关经典分析局限性的知识应该在其他领域有用。 该项目中开发的计算机技术可适用于其他领域，并将在未来几年对其他研究人员有用。 此外，非常重要的是，该项目的特点是本科生物理系学生的广泛参与。 他们不仅可以通过增加该领域的知识和提高计算机技能而受益，还可以通过思维技能和智力习惯的发展而受益。