Numerical study on aging dynamics in the 3D Ising spin-glass model －quasi-equilibrium behavior of spin auto-correlation functions

摘要

Using Monte Carlo simulations, we have studied aging phenomena in three-dimensional Gaussian Ising-glass model focusing on quasi-equilibrium behavior of the spin autocorrelation functions. Weak violation of the time translational invariance in the quasi-equilibrium regime is analyzed in terms of effective stiffness for droplet excitations in the presence of domain is walls. The simulation results not only in isothermal aging but also in T-shift aging process. T-shift aging processes exhibit the expected scaling behavior with respect to the characteristic length scales associated with droplet excitations and domain walls in spite of the fact that the growth law for these length scales still shows a preasymptotic behavior compared with the asymptotic from proposed by the droplet theory Implications of our simulational results are also discussed in relation to experimental observations.