Calculating the Relative Variances of Magnetization, Heat Capacity, and Susceptibility in a Two-Dimensional Weakly Diluted Four-Component Potts Model

The relative variances of the magnetization R m , heat capacity R c , and susceptibility R χ are calculated by the Monte Carlo method in the spin lattice four-component weakly diluted Potts model on a square lattice at a spin density p = 0.80. It is shown that introducing a disorder in the form of nonmagnetic impurities into the 2D Potts model leads to nonzero values of R m , R c , and R χ at the critical point. It has been found that these values decrease noticeably for systems with linear sizes L ≥ 120 interatomic distances.