% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@PHDTHESIS{Ikonomov:40409,
      author       = {Ikonomov, Julian Borislavov},
      title        = {{STM} studies of islands on {C}u and {P}t surfaces},
      volume       = {4144},
      issn         = {0944-2952},
      school       = {Univ. Düsseldorf},
      type         = {Dr. (Univ.)},
      address      = {Jülich},
      publisher    = {Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag},
      reportid     = {PreJuSER-40409, Juel-4144},
      series       = {Berichte des Forschungszentrums Jülich},
      pages        = {84 p.},
      year         = {2004},
      note         = {Record converted from VDB: 12.11.2012; Düsseldorf, Univ.,
                      Diss., 2004},
      abstract     = {This thesis deals with quantitative studies of equilibrium
                      and non-equilibrium phenomena on Pt(III) and Cu(100)
                      surfaces using scanning tunneling microscopy (STM). The aim
                      of this work is apply theoretical methods based on
                      statistical physics to determine atomistic energy parameters
                      of surface diffusion processes on metal substrates which
                      cannot be directly detected, and hence, analyzed as
                      individual atomic hopping events. As was shown previously,
                      one may determine activation barriers of diffusion,
                      pre-exponential factors and formation energies. In this
                      thesis, the theoretical methods were applied to Pt(111) and
                      Cu(100) substrates and step free energies were measured,
                      dominant mass transport processes were identified and the
                      relevant activation energies were obtained. On Pt(III), for
                      instance, the equilibrium shape and the equilibrium edge
                      fluctuations of monatomic high islands were studied between
                      533 K and 713 K. Using the measured equilibrium shapes, the
                      ratio between the step free energies of A- and B-steps on
                      Pt(111) was analyzed for the first time as a function of
                      temperature. Using the relatively new method of island edge
                      fluctuation studies, absolute values for the free energies
                      for A- and B-steps on Pt(111) could be determined
                      experimentally for the first time. As a non-equilibrium
                      phenomena, the Ostwald ripening of single-layer deep vacancy
                      islands on Cu(100) was investigated between 323 K and 398 K.
                      A previous result could be confirmed that the mono-vacancies
                      are the dominant mass transport species on Cu(100). From the
                      temperature dependence of the decay rate, the relevant
                      activation energy have been obtained. Comparing the
                      activation energy found in this thesis with previous
                      measurements allowed the determination of the sticking
                      barrier of mono-vacancies at vacancy island edges on
                      Cu(100). A further island decay process was studied in this
                      work which has been discovered only recently to accelerate
                      island decay on fcc(111) surfaces, the rapid island decay.
                      In this thesis, it is shown that this fast decay channel
                      exists also on Pt(111). Finally, a coarsening process is
                      discussed which has a great importance on fcc (100)
                      surfaces, the island coalescence. Here, the coalescence of
                      single-layer deep vacancy islands on Cu(100) was
                      investigated between 303 K and 353 K. It could be shown that
                      the equilibration of the island shape after coalescence is
                      dominated by atom diffusion along the island edges. The
                      relevant activation energy was determined and the result
                      corroborates recent preliminary studies of fluctuations of
                      highly-kinked steps which showed that the activation energy
                      is much lower compared to the energy measured for steps
                      along the atomically dense direction.},
      cin          = {ISG-4},
      cid          = {I:(DE-Juel1)VDB44},
      pnm          = {Kondensierte Materie},
      pid          = {G:(DE-Juel1)FUEK242},
      typ          = {PUB:(DE-HGF)11 / PUB:(DE-HGF)3},
      url          = {https://juser.fz-juelich.de/record/40409},
}