Spectroscopy and dynamics of electron excitations of supported metal clusters

该项目的主要目标是研究负载金属团簇与激光诱导电子激发。在焦点是集体激发，以及单电子激发的集群和衬底表面和它们的修改作为集群-衬底相互作用的结果。特别是，我们感兴趣的集群定位的激发所提供的基板的新的衰变通道的效果。我们预计，相应的寿命可以淬火到几个飞秒范围内的时间尺度，只有。拟议的项目将专门集中在尺寸选定的金属簇沉积在定义的金属单晶表面。对于系统的研究，我们计划簇和衬底材料，衬底取向和簇大小的变化。应用的主要技术是双光子光电发射和时间分辨光电发射电子显微镜。对于我们的样品的横向表征，将使用原位扫描探针显微镜。电子激发已被证明是表面化学反应的显着相关性。接下来的基本兴趣的原则，簇表面相互作用，我们预计，从这个项目的结果将有影响的催化过程的理解支持集群。

The main goal of the project is the study of supported metal clusters with respect to laser induced electronic excitations. In focus are collective excitations as well as single electron excitations of clusters and substrate surfaces and their modification as a result of cluster-substrate interaction. In particular we are interested in the effect of new decay channels for the cluster located excitations as offered by the substrate. We expect that the corresponding lifetimes can be quenched down to time-scales in the range of a few femtoseconds, only. The proposed project will exclusively focus on size selected metal clusters deposited on defined metal single crystalline surfaces. For systematic studies we plan variations of cluster and substrate material, substrate orientation and cluster size. The principle techniques applied are Two Photon Photoemission and time-resolved Photoemission Electron Microscopy. For lateral characterization of our samples an in-situ scanning probe microscope will be used. Electronic excitations have been shown to be of significant relevance for surface chemical reactions. Next to the fundamental interest in the principles of cluster-surface interaction we expect that the results from this project will have impact on the understanding of catalytic processes at supported clusters.