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Title: Elastic lattice in an incommensurate background

Abstract

We study a harmonic triangular lattice, which relaxes in the presence of an incommensurate short-wavelength potential. Monte Carlo simulations reveal that the elastic lattice exhibits only short-ranged translational correlations, despite the absence of defects in either lattice. Extended orientational order, however, persists in the presence of the background. Translational correlation lengths exhibit approximate power-law dependence upon cooling rate and background strength. Our results may be relevant to Wigner crystals, atomic monolayers on crystals surfaces, and flux-line and magnetic bubble lattices.

Authors:
;  [1]
  1. (Department of Physics and Astronomy, Lehman College, City University of New York, Bedford Park Boulevard West, Bronx, New York 10468-1589 (United States))
Publication Date:
OSTI Identifier:
6692556
Alternate Identifier(s):
OSTI ID: 6692556
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review, B: Condensed Matter; (United States); Journal Volume: 51:1
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTAL LATTICES; RELAXATION; COMPUTERIZED SIMULATION; ELASTICITY; HARMONIC OSCILLATOR MODELS; MONTE CARLO METHOD; TWO-DIMENSIONAL CALCULATIONS; CALCULATION METHODS; CRYSTAL STRUCTURE; MATHEMATICAL MODELS; MECHANICAL PROPERTIES; SIMULATION; TENSILE PROPERTIES 665000* -- Physics of Condensed Matter-- (1992-)

Citation Formats

Dickman, R., and Chudnovsky, E.M. Elastic lattice in an incommensurate background. United States: N. p., 1995. Web. doi:10.1103/PhysRevB.51.97.
Dickman, R., & Chudnovsky, E.M. Elastic lattice in an incommensurate background. United States. doi:10.1103/PhysRevB.51.97.
Dickman, R., and Chudnovsky, E.M. Sun . "Elastic lattice in an incommensurate background". United States. doi:10.1103/PhysRevB.51.97.
@article{osti_6692556,
title = {Elastic lattice in an incommensurate background},
author = {Dickman, R. and Chudnovsky, E.M.},
abstractNote = {We study a harmonic triangular lattice, which relaxes in the presence of an incommensurate short-wavelength potential. Monte Carlo simulations reveal that the elastic lattice exhibits only short-ranged translational correlations, despite the absence of defects in either lattice. Extended orientational order, however, persists in the presence of the background. Translational correlation lengths exhibit approximate power-law dependence upon cooling rate and background strength. Our results may be relevant to Wigner crystals, atomic monolayers on crystals surfaces, and flux-line and magnetic bubble lattices.},
doi = {10.1103/PhysRevB.51.97},
journal = {Physical Review, B: Condensed Matter; (United States)},
number = ,
volume = 51:1,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1995},
month = {Sun Jan 01 00:00:00 EST 1995}
}
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  • The phase diagram of the two-dimensional lattice-gas ANNNI model is investigated using the cluster transfer-matrix method. The numerical calculations have shown commensurate, disordered, and floating incommensurate phases. The properties of the incommensurate phase are studied in detail and the position of the Lifshitz point is discussed.
  • It is known that microwave dielectric ZrTiO{sub 4} undergoes a normal-to-incommensurate phase transition (NICPT) near 1125{degree}C. The role of the cation ordering and its relation to the anomalous lattice contraction observed in the NICPT were studied by x-ray diffraction and Raman scattering of ZrTiO{sub 4} specimens prepared employing various cooling rates between 1250 and 1000{degree}C. It was shown that the lattice parameter b underwent a substantial change even if the long-range cation ordering was absent. Analysis of the Raman spectra indicated that the compositional fluctuation-induced line broadening was mainly responsible for the extrapolated linewidth at 0 K, suggesting that themore » observed lattice contraction was initiated by the local short-range cation ordering. Based on thermodynamic arguments, the anomalous lattice contraction of ZrTiO{sub 4} was attributed to a direct consequence of the gradient coupling between the two order parameters that describe a compositional modulation and a displacive modulation in the NICPT. {copyright} 2001 American Institute of Physics.« less
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  • No abstract prepared.