Calculation of relative dispersions of magnetization, heat capacity and susceptibility in a two-dimensional weakly diluted 3-state Potts model

Using the Monte Carlo method, the relative dispersions of magnetization $R_m$, heat capacity $R_c$ and susceptibility $R_\chi$ are calculated for a weakly diluted 3-state Potts model on a square lattice at a spin concentration $p$ = 0.90. It is revealed that the introduction of disorder in the form of nonmagnetic impurities into the two-dimensional Potts model leads to non-zero values for $R_m$, $R_c$, $R_\chi$ at the critical point. It is found that these values decrease markedly for systems with linear dimensions $L>$ 40.