Local correlation of photoemission electron microscopy and STM at a defined cluster substrate system

We describe a technique that enables photoelectron spectroscopy and STM imaging of supported clusters from identical surface areas of a size of a few mu m(2) at a lateral resolution in the low nanometer regime. In this way we are able to locally correlate properties regarding the electronic structure of the clusters and their topography. The use of a photoemission electron microscope (PEEM) allows one to probe the local distribution of the photoemission yield. An STM-tip is used to remove clusters from their position and set local, well-defined markers at the surface that are clearly visible in the PEEM images. These markers act as reference points to identify surface areas in the PEEM image that have formerly been imaged by an STM. The present accuracy of this local correlation technique is at least 300 nm. We propose a scheme to further improve this correlation so that in future experiments even selected single clusters, which have been characterized by STM, can be addressed by local photoelectron spectroscopy as well as local time-resolved photoelectron spectroscopy.