Electron pair emission from a W(001) surface: Photon versus electron excitation

Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany.
Journal of Physics Condensed Matter (Impact Factor: 2.35). 09/2009; 21(35):355003. DOI: 10.1088/0953-8984/21/35/355003
Source: PubMed


The electron pair emission from a W(001) surface was studied using a coincidence
time-of-flight spectrometer. The aim of this study was to compare the pair emission upon
electron impact and upon photon absorption. The energy distributions are markedly
different for these two experiments. From this we conclude that the photon-stimulated pair
emission carries a significant contribution from a double photoemission process, while the
process of first creating a photoelectron, which in a subsequent collision leads to pair
emission, is of less importance.

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