Spectroscopy and dynamics of electron excitations of supported metal clusters

点击翻译按钮获取中文摘要

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.