RUI: Spatial and Temporal Dynamics of Matter in Intense Laser Fields

世界各地的实验室已经开始开发高功率激光系统，该系统可以产生能量如此之高的电磁辐射脉冲，从而开辟了新的探索途径。本项目将通过具有足够时间和空间分辨率的从头算计算机模拟来协助这些令人兴奋的发展，以提供对光子与电子和正电子的相对论相互作用的微观洞察。 更好地理解这些基本过程可能会开辟新的方法来控制原子，化学甚至生物过程在很短的时间尺度。 该补助金的一个重要使命也是让本科生有机会获得研究经验。 这种教育经历为他们提供了重要的技能，包括作为一个团队工作，获得耐力，智力灵活性和经验，以解决严重的研究问题，并在会议和出版物中交流结果。计算机模拟是通过在数值时空网格上求解相对论量子电动力学的Dirac-Maxwell方程组来获得的。 这些非微扰的大规模计算是非常耗时的CPU，但已成为可能，由于最近的进展，在大规模并行计算机的专门数值算法的发展。 计算在伊利诺伊州进行。 这项工作的一些主要目标包括通过合适的激光场设计优化对产生产率，开发更有效的广义相对论相互作用方法，利用几种物理机制来降低对所需的激光强度，该奖项反映了NSF的法定使命，并被认为值得支持通过使用基金会的知识价值和更广泛的影响审查标准进行评估。

Laboratories across the world have begun to develop high-powered laser systems which can create electromagnetic radiation pulses that are so energetic that they open new avenues of exploration. This project will assist these exciting developments with ab initio computer simulations which have sufficient temporal and spatial resolution to provide microscopic insight into the relativistic interaction of photons with electrons and positrons. A better understanding of these fundamental processes might open new ways to control atomic, chemical and even biological processes on very short time scales. An important mission for the grant is also to give undergraduate students the opportunity to gain research experience. This educational experience provides them with important skills including working as a team, gaining the endurance, intellectual flexibility and experience to tackle serious research problems, and communicating results in conferences and publications.The computer simulations are obtained by solving the coupled set of Dirac-Maxwell equations of relativistic quantum electrodynamics on a numerical space-time grid. These non-perturbative large-scale calculations are very CPU time consuming but have become possible due to recent progress in the development of specialized numerical algorithms for massively parallel computers. The calculations are performed in Illinois. Some of the primary goals of the work include optimizing the pair creation yield by suitable laser field designs, developing more efficient approaches for general relativistic interactions, exploiting several physical mechanisms to lower the laser intensity required for pair-creation and providing a new diagnostic technique to monitor the creation dynamics inside the reaction zone.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.