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Title: Chiral symmetry restoration in anisotropic QED{sub 3}

Abstract

We present results from a Monte Carlo simulation of noncompact lattice QED in three dimensions in which an explicit anisotropy {kappa} between x and y hopping terms has been introduced into the action. Using a parameter set corresponding to broken chiral symmetry in the isotropic limit {kappa}=1, we study the chiral condensate on 16{sup 3}, 20{sup 3}, and 24{sup 3} lattices as {kappa} is varied, and fit the data to an equation of state which incorporates anisotropic volume corrections. The value {kappa}{sub c} at which chiral symmetry is apparently restored is strongly volume dependent, suggesting that the transition may be a crossover rather than a true phase transition. In addition we present results on 16{sup 3} lattices for the scalar meson propagator, and for the Landau gauge-fixed fermion propagator. The scalar mass approaches the pion mass at large {kappa}, consistent with chiral symmetry restoration, but the fermion remains massive at all values of {kappa} studied, suggesting that strong infrared fluctuations persist into the chirally symmetric regime. Implications for models of high-T{sub c} superconductivity based on anisotropic QED{sub 3} are discussed.

Authors:
 [1];  [2]
  1. Department of Physics, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom)
  2. Department of Physics, Swansea University, Singleton Park, Swansea SA2 8PP (United Kingdom)
Publication Date:
OSTI Identifier:
20957792
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.75.134516; (c) 2007 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; 36 MATERIALS SCIENCE; ANISOTROPY; CHIRAL SYMMETRY; COMPUTERIZED SIMULATION; EQUATIONS OF STATE; FERMIONS; FLUCTUATIONS; HIGH-TC SUPERCONDUCTORS; LATTICE FIELD THEORY; MONTE CARLO METHOD; PIONS; QUANTUM ELECTRODYNAMICS; SCALAR MESONS; SUPERCONDUCTIVITY; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Thomas, Iorwerth Owain, and Hands, Simon. Chiral symmetry restoration in anisotropic QED{sub 3}. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.134516.
Thomas, Iorwerth Owain, & Hands, Simon. Chiral symmetry restoration in anisotropic QED{sub 3}. United States. doi:10.1103/PHYSREVB.75.134516.
Thomas, Iorwerth Owain, and Hands, Simon. Sun . "Chiral symmetry restoration in anisotropic QED{sub 3}". United States. doi:10.1103/PHYSREVB.75.134516.
@article{osti_20957792,
title = {Chiral symmetry restoration in anisotropic QED{sub 3}},
author = {Thomas, Iorwerth Owain and Hands, Simon},
abstractNote = {We present results from a Monte Carlo simulation of noncompact lattice QED in three dimensions in which an explicit anisotropy {kappa} between x and y hopping terms has been introduced into the action. Using a parameter set corresponding to broken chiral symmetry in the isotropic limit {kappa}=1, we study the chiral condensate on 16{sup 3}, 20{sup 3}, and 24{sup 3} lattices as {kappa} is varied, and fit the data to an equation of state which incorporates anisotropic volume corrections. The value {kappa}{sub c} at which chiral symmetry is apparently restored is strongly volume dependent, suggesting that the transition may be a crossover rather than a true phase transition. In addition we present results on 16{sup 3} lattices for the scalar meson propagator, and for the Landau gauge-fixed fermion propagator. The scalar mass approaches the pion mass at large {kappa}, consistent with chiral symmetry restoration, but the fermion remains massive at all values of {kappa} studied, suggesting that strong infrared fluctuations persist into the chirally symmetric regime. Implications for models of high-T{sub c} superconductivity based on anisotropic QED{sub 3} are discussed.},
doi = {10.1103/PHYSREVB.75.134516},
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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