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Title: Exact linear response of reacting thermal defects driven by creation processes

Abstract

The exact, linear response at steady state is calculated for reacting, but otherwise noninteracting, thermal defects driven by defect creation processes. The theory applies to vacancies and interstitials in the bulk, or to adatoms and advacancies on surface terraces. A wide variety of possible driving forces includes nuclear reaction, particle irradiation, epitaxial growth, surface erosion, and sublimation. When the defect life cycle typically starts and ends with spontaneous pair creation and annihilation, both species respond to the difference of their separate driving terms (the ''Poisson'' regime), and the law of mass action holds everywhere with a position dependent chemical potential {mu}*(r). The value of {mu}*(r) in linear response is employed here to discuss the conditions under which thermal defects precipitate, particularly as islands on terraces and dislocation loops in the bulk. It is shown, for the Poisson regime, that an approximate symmetry exists between processes for the two antidefects. Specifically, if {mu}{sub c}* suffices to nucleate a precipitate of one antidefect, then -{mu}{sub c}* is required to nucleate the other.

Authors:
 [1]
  1. Physics Department and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)
Publication Date:
OSTI Identifier:
20957786
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 13; Other Information: DOI: 10.1103/PhysRevB.75.134106; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNIHILATION; DEFECTS; DISLOCATIONS; EPITAXY; INTERSTITIALS; IRRADIATION; MUONS MINUS; NUCLEATION; PAIR PRODUCTION; PRECIPITATION; STEADY-STATE CONDITIONS; SUBLIMATION; SURFACES; VACANCIES

Citation Formats

Flynn, C. P. Exact linear response of reacting thermal defects driven by creation processes. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.134106.
Flynn, C. P. Exact linear response of reacting thermal defects driven by creation processes. United States. doi:10.1103/PHYSREVB.75.134106.
Flynn, C. P. Sun . "Exact linear response of reacting thermal defects driven by creation processes". United States. doi:10.1103/PHYSREVB.75.134106.
@article{osti_20957786,
title = {Exact linear response of reacting thermal defects driven by creation processes},
author = {Flynn, C. P.},
abstractNote = {The exact, linear response at steady state is calculated for reacting, but otherwise noninteracting, thermal defects driven by defect creation processes. The theory applies to vacancies and interstitials in the bulk, or to adatoms and advacancies on surface terraces. A wide variety of possible driving forces includes nuclear reaction, particle irradiation, epitaxial growth, surface erosion, and sublimation. When the defect life cycle typically starts and ends with spontaneous pair creation and annihilation, both species respond to the difference of their separate driving terms (the ''Poisson'' regime), and the law of mass action holds everywhere with a position dependent chemical potential {mu}*(r). The value of {mu}*(r) in linear response is employed here to discuss the conditions under which thermal defects precipitate, particularly as islands on terraces and dislocation loops in the bulk. It is shown, for the Poisson regime, that an approximate symmetry exists between processes for the two antidefects. Specifically, if {mu}{sub c}* suffices to nucleate a precipitate of one antidefect, then -{mu}{sub c}* is required to nucleate the other.},
doi = {10.1103/PHYSREVB.75.134106},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 13,
volume = 75,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}
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