Critical behavior and lack of selfaveraging in the dynamics of the random Potts model in two dimensions
Abstract
We study the dynamics of the qstate random bond Potts ferromagnet on the square lattice at its critical point by Monte Carlo simulations with single spinflip 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 τ at the critical point is finite. However, for q=24 this appears to diverge in the thermodynamic limit and it is ln τ 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.
 Publication:

Physical Review B
 Pub Date:
 July 2002
 DOI:
 10.1103/PhysRevB.66.014438
 arXiv:
 arXiv:condmat/0202135
 Bibcode:
 2002PhRvB..66a4438D
 Keywords:

 75.40.Cx;
 75.50.Lk;
 05.50.+q;
 75.40.Mg;
 Static properties;
 Spin glasses and other random magnets;
 Lattice theory and statistics;
 Numerical simulation studies;
 Condensed Matter  Disordered Systems and Neural Networks;
 Condensed Matter  Statistical Mechanics
 EPrint:
 9 pages, 13 figures, final published version