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arXiv · hep-lat/0609062

Chiral Symmetry Restoration in Anisotropic QED(3)

Abstract

We present results from a Monte Carlo simulation of non-compact lattice QED in 3 dimensions in which an explicit anisotropy $κ$ 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 $κ=1$, we study the chiral condensate on $16^3$, $20^3$, and $24^3$ lattices as $κ$ is varied, and fit the data to an equation of state which incorporates anisotropic volume corrections. The value $κ_c$ at which chiral symmetry ispparently 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 $16^3$ lattices for the scalar meson propagator, and for the Landau gauge-fixed fermion propagator. The scalar mass approaches the pion mass at large $κ$, consistent with chiral symmetry restoration, but the fermion remains massive at all values of $κ$ studied, suggesting that strong infra-red fluctuations persist into the chirally symmetric regime. Implications for models of high-$T_c$ superconductivity based on anisotropic QED$_3$ are discussed.

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BibTeXRIS

Iorwerth Owain Thomas, Simon Hands. 2006-09-28. Chiral Symmetry Restoration in Anisotropic QED(3). https://doi.org/10.1103/physrevb.75.134516

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