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Title: Correlations in nanoscale step fluctuations: Comparison of simulation and experiments

Abstract

We analyze correlations in step-edge fluctuations using the Bortz-Kalos-Lebowitz kinetic Monte Carlo (MC) algorithm, with a two-parameter expression for energy barriers, and compare with our variable-temperature scanning tunneling microscopy line-scan experiments on spiral steps on Pb(111). The scaling of the correlation times gives a dynamic exponent confirming the expected step-edge-diffusion rate-limiting kinetics both in the MC simulations and in the experiments. We both calculate and measure the temperature dependence of (mass) transport properties via the characteristic hopping times and deduce therefrom the notoriously elusive effective energy barrier for the edge fluctuations. With a careful analysis we point out the necessity of a more complex model to mimic the kinetics of a Pb(111) surface for certain parameter ranges.

Authors:
; ; ;  [1];  [1];  [2];  [3]
  1. Department of Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)
  2. (United States)
  3. Center for Computational Materials Science, Naval Research Laboratory, Washington, DC 20375-5343 (United States)
Publication Date:
OSTI Identifier:
20788010
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevB.73.115413; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALGORITHMS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; CORRELATIONS; DIFFUSION; FLUCTUATIONS; KINETICS; MONTE CARLO METHOD; NANOSTRUCTURES; SCANNING TUNNELING MICROSCOPY; SURFACES; TEMPERATURE DEPENDENCE

Citation Formats

Szalma, F., Degawa, M., Williams, Ellen D., Einstein, T. L., Dougherty, D. B., Department of Chemistry, Surface Science Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, and Haftel, Michael I. Correlations in nanoscale step fluctuations: Comparison of simulation and experiments. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.1.
Szalma, F., Degawa, M., Williams, Ellen D., Einstein, T. L., Dougherty, D. B., Department of Chemistry, Surface Science Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, & Haftel, Michael I. Correlations in nanoscale step fluctuations: Comparison of simulation and experiments. United States. doi:10.1103/PHYSREVB.73.1.
Szalma, F., Degawa, M., Williams, Ellen D., Einstein, T. L., Dougherty, D. B., Department of Chemistry, Surface Science Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, and Haftel, Michael I. Wed . "Correlations in nanoscale step fluctuations: Comparison of simulation and experiments". United States. doi:10.1103/PHYSREVB.73.1.
@article{osti_20788010,
title = {Correlations in nanoscale step fluctuations: Comparison of simulation and experiments},
author = {Szalma, F. and Degawa, M. and Williams, Ellen D. and Einstein, T. L. and Dougherty, D. B. and Department of Chemistry, Surface Science Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 and Haftel, Michael I.},
abstractNote = {We analyze correlations in step-edge fluctuations using the Bortz-Kalos-Lebowitz kinetic Monte Carlo (MC) algorithm, with a two-parameter expression for energy barriers, and compare with our variable-temperature scanning tunneling microscopy line-scan experiments on spiral steps on Pb(111). The scaling of the correlation times gives a dynamic exponent confirming the expected step-edge-diffusion rate-limiting kinetics both in the MC simulations and in the experiments. We both calculate and measure the temperature dependence of (mass) transport properties via the characteristic hopping times and deduce therefrom the notoriously elusive effective energy barrier for the edge fluctuations. With a careful analysis we point out the necessity of a more complex model to mimic the kinetics of a Pb(111) surface for certain parameter ranges.},
doi = {10.1103/PHYSREVB.73.1},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 11,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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