Dresden 2003 – wissenschaftliches Programm

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DY: Dynamik und Statistische Physik

DY 27: Growth processes and interface features II

DY 27.3: Vortrag

Dienstag, 25. März 2003, 17:15–17:30, G\"OR/229

Density based kinetic Monte Carlo methods: Fundamentals and Applications — •Lorenzo Mandreoli and Jörg Neugebauer — Fritz-Haber-Institut der MPG, Berlin, Germany

The method of choice for atomic scale epitaxial growth simulations is kinetic Monte Carlo (kMC). Characteristic for this approach is that the trajectories of all atoms have to be explicitely calculated making it exceedingly expensive to describe the technologically important case of high temperature growth. We have therefore explored two alternative approaches which are based on adatom density rather than on trajectories: the single Adatom Density kinetic Monte Carlo (sAD-kMC) where for each adatom the density is calculated and the Adatom Density kinetic Monte Carlo (AD-kMC) where only the total density is calculated. Extensive tests of various statistical/structural properties (island size distribution, island density and island shape) and of nucleation processes on terraces and along the island edges show that sAD-kMC works for all temperatures including low temperature fractal growth. Our results further show that the computationally much more efficient AD-kMC method fails to describe low temperature growth but accurately reproduces high temperature results. Applications of the methods for various growth regimes will be discussed.