title: Spot profile analysis and lifetime mapping in ultrafast electron diffraction: Lattice excitation of self-organized Ge nanostructures on Si(001).
abstract: Ultrafast high energy electron diffraction in reflection geometry is employed to study the structural dynamics of self-organized Germanium hut-, dome-, and relaxed clusters on Si(001) upon femtosecond laser excitation. Utilizing the difference in size and strain state the response of hut- and dome clusters can be distinguished by a transient spot profile analysis. Surface diffraction from {105}-type facets provide exclusive information on hut clusters. A pixel-by-pixel analysis of the dynamics of the entire diffraction pattern gives time constants of 40, 160, and 390 ps, which are assigned to the cooling time constants for hut-, dome-, and relaxed clusters.
authors.affiliation: Department of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , Lotharstr. 1, 47057 Duisburg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Frigge
authors.affiliation: Department of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , Lotharstr. 1, 47057 Duisburg, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Hafke
authors.affiliation: Department of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , Lotharstr. 1, 47057 Duisburg, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Tinnemann
authors.affiliation: Department of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , Lotharstr. 1, 47057 Duisburg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Witte
authors.affiliation: Department of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , Lotharstr. 1, 47057 Duisburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Horn-von Hoegen