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Title: Controlled selforganization of atom vacancies in monatomic gallium layers

Abstract

Ga adsorption on the Si(112) surface results in the formation of pseudomorphic Ga atom chains. Compressive strain in these atom chains is relieved via creation of adatom vacancies and their selforganization into meandering vacancy lines. The average spacing between these line defects can be controlled, within limits, by adjusting the chemical potential of the Ga adatoms. We derive a lattice model that quantitatively connects density functional theory (DFT) calculations for perfectly ordered structures with the fluctuating disorder seen in experiment and the experimental control parameter. This hybrid approach of lattice modeling and DFT can be applied to other examples of line defects in heteroepitaxy.

Authors:
 [1];  [1];  [2];  [2];  [2];  [1]
  1. ORNL
  2. Universidad Autonoma de Madrid, Madrid
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
930945
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 99; Journal Issue: 2007
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GALLIUM; ADSORPTION; SILICON; SORPTIVE PROPERTIES; DENSITY FUNCTIONAL METHOD; LINE DEFECTS; STRAINS; VACANCIES; MATHEMATICAL MODELS; Atom; vacancies; monatomic; gallium

Citation Formats

Snijders, Paul C, Moon, Eun Ju, Gonzalez, C., Ortega, J., Flores, F., and Weitering, Harm H. Controlled selforganization of atom vacancies in monatomic gallium layers. United States: N. p., 2007. Web. doi:10.1103/PhysRevLett.99.116102.
Snijders, Paul C, Moon, Eun Ju, Gonzalez, C., Ortega, J., Flores, F., & Weitering, Harm H. Controlled selforganization of atom vacancies in monatomic gallium layers. United States. doi:10.1103/PhysRevLett.99.116102.
Snijders, Paul C, Moon, Eun Ju, Gonzalez, C., Ortega, J., Flores, F., and Weitering, Harm H. Mon . "Controlled selforganization of atom vacancies in monatomic gallium layers". United States. doi:10.1103/PhysRevLett.99.116102.
@article{osti_930945,
title = {Controlled selforganization of atom vacancies in monatomic gallium layers},
author = {Snijders, Paul C and Moon, Eun Ju and Gonzalez, C. and Ortega, J. and Flores, F. and Weitering, Harm H},
abstractNote = {Ga adsorption on the Si(112) surface results in the formation of pseudomorphic Ga atom chains. Compressive strain in these atom chains is relieved via creation of adatom vacancies and their selforganization into meandering vacancy lines. The average spacing between these line defects can be controlled, within limits, by adjusting the chemical potential of the Ga adatoms. We derive a lattice model that quantitatively connects density functional theory (DFT) calculations for perfectly ordered structures with the fluctuating disorder seen in experiment and the experimental control parameter. This hybrid approach of lattice modeling and DFT can be applied to other examples of line defects in heteroepitaxy.},
doi = {10.1103/PhysRevLett.99.116102},
journal = {Physical Review Letters},
number = 2007,
volume = 99,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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