Theory of Atomic, Molecular, and Optical Processes

这项建议涉及广泛的原子、分子和光学(AMO)过程的全面理论研究，这些过程在当前的科学和技术中具有重要意义。建议的活动将建立在我们过去的努力和非微扰理论形式和高精度计算方法的新发展的基础上，以精确处理高激发态和多激发态的电子结构，以及在存在强外场的情况下的多光子动力学和原子和分子过程的相干控制。本提议的第一部分重点涉及高频VUV/XUV区高次谐波产生(HHG)谱的频率梳结构和各阶相干性的从头算理论探索。频率梳工程的研究将发展两种方法：(A)用含时广义伪谱方法(TDGPS)在空间和时间上精确高效地求解含时薛定谔方程(TDSE)；(B)用多模Floquet理论(MMFT)。这个提议的第二部分将涉及里德堡原子中通过顺序跃迁或多光子绝热快速通过的布居转移的相干控制的研究。在该提案的最后部分，将介绍几个更大范围的项目，包括(A)发展一种新的超球坐标下的TDGPS方法，用于在外场存在下对双电子原子的双激发共振态和双光电离动力学进行完全从头算6D处理，以及(B)进一步发展无自相互作用的含时密度泛函理论(TDDFT)来探索多电子里德堡原子动力学。

This proposal addresses comprehensive theoretical investigation of a broad range ofatomic, molecular, and optical (AMO) processes of current significance in science andtechnology. The proposed activities will build on both of our past efforts and the newdevelopment of nonperturbative theoretical formalisms and high-precisioncomputational methods for accurate treatment of both the electronic structure of highlyand multiply excited states as well as the multiphoton dynamics and coherent control ofatomic and molecular processes in the presence of intense external fields.Emphasis in the first part of this proposal concerns the ab initio theoretical exploration ofthe frequency comb structure and coherence within each order of the high-orderharmonic generation (HHG) spectrum in the high-frequency VUV/XUV regime. Twoapproaches will be developed for the study of frequency comb projects: (a)time-dependent generalized pseudospectral method (TDGPS) for accurate and efficientsolution of the time-dependent Schrdinger equation (TDSE) in space and time, and (b)many-mode Floquet theory (MMFT). The second part of this proposal will deal with thestudy of the coherent control of population transfer in Rydberg atoms via sequentialtransitions or via multiphoton adiabatic rapid passage. In the last part of the proposal,several longer range projects will be presented, including (a) the development of a newTDGPS method in hyperspherical coordinates for fully ab initio 6D treatment of doublyexcited resonance states and double photoionization dynamics of two-electron atoms inthe presence of external fields, and (b) the further development of theself-interaction-free time-dependent density functional theory (TDDFT) for theexploration of many-electron Rydberg atom dynamics.