Dynamics of Clusters Controlled by Intense Laser Pulses

强激光脉冲与原子团簇的相互作用需要考虑从激光-固体到激光-气体相互作用的各种物理问题。单个团簇是通过在气体喷射膨胀中使原子/分子范德华键合而形成的直径达~1000A的原子聚集体。团簇内密度是固体的密度，而通过喷嘴膨胀形成的团簇气体要小得多。因此，激光脉冲与纳米级固体(单个星团)局部相互作用，但仍将大块介质视为气体，它可以通过它进行传播。因此，超短激光-团簇相互作用的物理具有传统激光-固体靶实验和激光-气体实验都没有实现的全新特征。该项目将进一步探索该小组开发的激光-星系团相互作用模型的影响，但尚未经过测试。将特别注意强激光加热星团的强压缩的研究。在第二组更实用的实验中，将继续研究强激光低温稀有气体液滴相互作用产生的极端紫外线和X射线辐射。这项工作对下一代光刻的极紫外线(EUV)源的开发具有直接的意义。

The interaction of intense laser pulses with atomic clusters requires consideration of physics spanning the range from laser-solid to laser-gas interaction. Individual clusters are atomic aggregates up to ~1000 A in diameter formed through van der Waals bonding of atoms/molecules in a gas jet expansion. Intra-cluster density is that of a solid, while a gas of clusters formed through nozzle expansion is much less. The laser pulse therefore interacts locally with nanoscale solids (the individual clusters), yet sees the bulk medium as a gas through which it can propagate. Thus, the physics of ultrashort laser-cluster interaction has completely new features not realized either in traditional laser-solid target experiments or in laser-gas experiments. This project will explore further, and as yet untested, implications of a laser-cluster interaction model developed by the group. Specific attention will be paid to the investigation of strong compressions of intense laser-heated clusters. In a second, more applied, set of experiments, work will continue on the study of extreme ultraviolet and x-ray emission from intense laser cryogenic noble-gas droplet interactions. This work has direct implications for extreme ultraviolet (EUV) source development for next-generation lithography.