engleski

Solution of a constrained Potts model in the mean- field limit

We study the q-state Potts model with constraint that each spin can assume only (q-1) of possible q states, the inaccessible state being chosen at random through the lattice. In the mean-field limit the exact analytic solution can be derived. We present the results for the cases q=3 and q=4, which exhibit the second and first-order phase transition respectively. We also examine the partition function zeros in the complex- temperature plane for this model. The convergence of the zero closest to the real axis can be related to the critical exponent $\nu$ and confirms the results obtained for the critical exponents in the case q=3 and the first-order character of the transition in the case q=4.

partition funcition zeroes ; Potts model

nije evidentirano