Off equilibrium dynamics in the 2d-XY system
Laboratoire de Physique des Matériaux, UMR CNRS No. 7556, Université Henri
Poincaré (Nancy 1), B.P. 239, 54506 Vandœuvre-lès-Nancy Cedex,
Corresponding author: a email@example.com
Published online: 19 February 2004
We study the non-equilibrium time evolution of the classical XY spin model in two dimensions. The two-time autocorrelation and linear response functions are considered for systems initially prepared in a high temperature state and in a completely ordered state. After a quench into the critical phase, we use Monte Carlo simulations to determine the time-evolution of these quantities, and we deduce the temperature dependence of the slope of the parametric plot susceptibility/correlation in the asymptotic regime. This slope is usually identified with the infinite fluctuation-dissipation ratio, which measures the extent of violation of the equilibrium fluctuation-dissipation theorem. However, a direct measure of this ratio leads to a vanishing value.
PACS: 75.40.Gb – Dynamic properties / 05.70.Ln – Non-equilibrium and irreversible thermodynamics
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004