Short-time critical dynamics of damage spreading in the two-dimensional Ising model

作者：Rubio Puzzo M Leticia; Albano Ezequiel V

来源：Physical Review E, 2010, 81(5): 051116.

DOI：10.1103/PhysRevE.81.051116

The short-time critical dynamics of propagation of damage in the Ising ferromagnet in two dimensions is studied by means of Monte Carlo simulations. Starting with equilibrium configurations at T=infinity and magnetization M=0, an initial damage is created by flipping a small amount of spins in one of the two replicas studied. In this way, the initial damage is proportional to the initial magnetization M-0 in one of the configurations upon quenching the system at T-C, the Onsager critical temperature of the ferromagnetic-paramagnetic transition. It is found that, at short times, the damage increases with an exponent theta(D)=1.915(3), which is much larger than the exponent theta=0.197 characteristic of the initial increase of the magnetization M(t). Also, an epidemic study was performed. It is found that the average distance from the origin of the epidemic (< R-2(t)>) grows with an exponent z* approximate to eta approximate to 1.9, which is the same, within error bars, as the exponent theta(D). However, the survival probability of the epidemics reaches a plateau so that delta=0. On the other hand, by quenching the system to lower temperatures one observes the critical spreading of the damage at T-D similar or equal to 0.

• 出版日期2010-5