Critical behavior and lack of self-averaging in the dynamics of the random Potts model in two dimensions

Article

关键词: 1ST-ORDER PHASE-TRANSITIONS;    CRITICAL DISORDERED-SYSTEMS;    MAGNETIC CRITICAL-BEHAVIOR;    MONTE-CARLO;   

DOI  :  10.1103/PhysRevB.66.014438

来源: SCIE

【 摘 要 】

We study the dynamics of the q-state random bond Potts ferromagnet on the square lattice at its critical point by Monte Carlo simulations with single spin-flip dynamics. We concentrate on q=3 and q=24 and find, in both cases, conventional, rather than activated, dynamics. We also look at the distribution of relaxation times among different samples, finding different results for the two q values. For q=3 the relative variance of the relaxation time tau at the critical point is finite. However, for q=24 this appears to diverge in the thermodynamic limit and it is ln tau which has a finite relative variance. We speculate that this difference occurs because the transition of the corresponding pure system is second order for q=3 but first order for q=24.

【 授权许可】

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