On universality in aging ferromagnets

Abstract

This work is a contribution to the study of universality in out-of-equilibrium lattice models undergoing a second-order phase transition at equilibrium. The experimental protocol that we have chosen is the following: the system is prepared in its high-temperature phase and then quenched at the critical temperature $T_c$. We investigated by mean of Monte Carlo simulations two quantities that are believed to take universal values: the exponent $\lambda /z$ obtained from the decay of autocorrelation functions and the asymptotic value $X_{\infty }$ of the fluctuation-dissipation ratio $X(t,s)$. This protocol was applied to the Ising model, the 3-state clock model and the 4-state Potts model on square, triangular and honeycomb lattices and to the Ashkin-Teller model at the point belonging at equilibrium to the 3-state Potts model universality class and to a multispin Ising model and the Baxter-Wu model both belonging to the 4-state Potts model universality class at equilibrium.

17 pages

References in corpus (2)

• Fluctuation-dissipation relations in the non-equilibrium critical dynamics of Ising models
• Bona Fide Thermodynamic Temperature in Nonequilibrium Kinetic Ising Models

Cited by in corpus (3)

• Activated aging dynamics and negative fluctuation-dissipation ratios
• Ageing phenomena without detailed balance: the contact process
• Ageing in the critical contact process: a Monte Carlo study