Universality of the Ratio of the Critical Amplitudes of the Magnetic Susceptibility in a TwoDimensional Ising Model with Nonmagnetic Impurities
Abstract
The behavior of the magnetic susceptibility of a twodimensional Ising model with nonmagnetic impurities is investigated numerically. A new method for determining the critical amplitudes and critical temperature is developed. The results of a numerical investigation of the ratio of the critical amplitudes of the magnetic susceptibility are presented. It is shown that the ratio of the critical amplitudes is universal right up to impurity concentrations q ≤ 0.25 (the percolation point of a square lattice is q_{c} = 0.407254). The behavior of the effective critical exponent γ(q) of the magnetic susceptibility is discussed. Apparently, a transition from Isingtype universal behavior to percolation behavior should occur in a quite narrow concentration range near the percolation point of the lattice.
 Publication:

Soviet Journal of Experimental and Theoretical Physics
 Pub Date:
 June 2000
 DOI:
 10.1134/1.559184
 Bibcode:
 2000JETP...90..964V
 Keywords:

 Spectroscopy;
 State Physics;
 Field Theory;
 Elementary Particle;
 Quantum Field Theory