12 research outputs found
Submonolayer growth with decorated island edges
We study the dynamics of island nucleation in the presence of adsorbates
using kinetic Monte Carlo simulations of a two-species growth model. Adatoms
(A-atoms) and impurities (B-atoms) are codeposited, diffuse and aggregate
subject to attractive AA- and AB-interactions. Activated exchange of adatoms
with impurities is identified as the key process to maintain decoration of
island edges by impurities during growth. While the presence of impurities
strongly increases the island density, a change in the scaling of island
density with flux, predicted by a rate equation theory for attachment-limited
growth [D. Kandel, Phys. Rev. Lett. 78, 499 (1997)], is not observed. We argue
that, within the present model, even completely covered island edges do not
provide efficient barriers to attachment.Comment: 7 pages, 2 postscript figure
Crossover effects in the Wolf-Villain model of epitaxial growth in 1+1 and 2+1 dimensions
A simple model of epitaxial growth proposed by Wolf and Villain is
investigated using extensive computer simulations. We find an unexpectedly
complex crossover behavior of the original model in both 1+1 and 2+1
dimensions. A crossover from the effective growth exponent to is observed in 1+1
dimensions, whereas additional crossovers, which we believe are to the scaling
behavior of an Edwards--Wilkinson type, are observed in both 1+1 and 2+1
dimensions. Anomalous scaling due to power--law growth of the average step
height is found in 1+1 D, and also at short time and length scales in 2+1~D.
The roughness exponents obtained from the
height--height correlation functions in 1+1~D () and 2+1~D
() cannot be simultaneously explained by any of the continuum
equations proposed so far to describe epitaxial growth.Comment: 11 pages, REVTeX 3.0, IC-DDV-93-00
Standards of rural municipalities in the Czech Republic and comparison with rural municipalities in Austria
This study was done on the request of the Ministry of Agriculture (MoACR). The purpose of this study was to define standards for rural municipalities (municipalities) and clarify this approach for assessment of the following measures in The Rural Development Plan 2014-2020. The assessment of standards shows how the principle is more preferred if it is the principle of cohesion in the area (disparity) or competitiveness and support of successful areas