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Zero-temperature criticality in the two-dimensional gauge glass model

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 نشر من قبل Lei-Han Tang
 تاريخ النشر 2004
  مجال البحث فيزياء
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The zero-temperature critical state of the two-dimensional gauge glass model is investigated. It is found that low-energy vortex configurations afford a simple description in terms of gapless, weakly interacting vortex-antivortex pair excitations. A linear dielectric screening calculation is presented in a renormalization group setting that yields a power-law decay of spin-wave stiffness with distance. These properties are in agreement with low-temperature specific heat and spin-glass susceptibility data obtained in large-scale multi-canonical Monte Carlo simulations.



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