Macroscopic Aspects of Ultrafast Strong-Field Atomic Physics

该奖项支持的研究解决了由于大量原子与强激光脉冲的极端非线性相互作用而产生的令人兴奋的现象。在这一过程中产生的相干极端紫外线(XUV)辐射为光谱学、相干控制和飞秒/阿秒动力学提供了一个独特和多功能的来源。该奖项的一些子项目将探索优化和控制XUV产生过程的新方法，其他子项目旨在使用XUV光作为产生它的量子动力学的诊断。这项工作将通过继续开发和应用从头算非绝热理论模型来完成，该模型用于气相中原子与超短激光脉冲的相互作用。这种“数值非线性介质”允许从第一性原理完全模拟最先进的短脉冲激光实验。大多数设想的计算都与正在进行的与处于超快强场物理前沿的四个实验小组的合作直接相关。相干、超快的XUV脉冲允许在几飞秒和亚飞秒的时间尺度上探测和操纵原子、分子和生物过程，从而产生了通过物质与光的相互作用来理解和控制物质的新方法。超快强场物理继续由欧洲集团主导，亚洲也在进行强有力的努力。该奖项支持的研究将加强美国在这一领域的存在，并将有助于培养这一原子、分子和光学科学这一交叉学科领域的下一代科学家。博士后研究人员和研究生/本科生将获得原子物理和高强度激光科学方面的广泛教育。通过与实验小组的密切合作，他们将对实验以及涉及的理论问题有一个透彻的了解。

The research supported by this award addresses the exciting phenomena resulting from the extremely nonlinear interaction of a macroscopic number of atoms with an intense laser pulse. The coherent extreme ultraviolet (XUV) radiation generated in this process presents a unique and versatile source for spectroscopy, coherent control, and femtosecond/attosecond dynamics. Some of the sub-projects of the award will explore novel ways to optimize and control the XUV generation process, and other sub-projects aim at using the XUV light as a diagnostic of the quantum dynamics that produced it. The work will be accomplished through the continued development and application of an ab-initio, non-adiabatic theoretical model for the interaction of atoms in the gas phase with ultrashort laser pulses. This "numerical non-linear medium" allows for the complete simulation of the most advanced short pulse laser experiments from first principles. The majority of the calculations envisioned are directly relevant to ongoing collaborations with four experimental groups at the forefront of ultrafast strong field physics. Coherent, ultrafast XUV pulses allow for probing and manipulating atomic, molecular and biological processes at few-femtosecond and sub-femtosecond time scales, yielding new ways to understand and control matter via its interaction with light. Ultrafast strong-field physics continues to be dominated by European groups, with strong efforts also underway in Asia. The research supported under this award will strengthen the US presence in this field, and will help train the next generation of scientists in this interdisciplinary field of atomic, molecular and optical science. Postdoctoral researchers and graduate/undergraduate students will gain a broad education in both atomic physics and high intensity laser science. Through close collaborations with experimental groups they will have a thorough understanding of the experimental as well as the theoretical issues involved.