title: Yang-Lee zeros and the critical behavior of the infinite-range two- and three-state Potts models.
abstract: The phase diagram of the two- and three-state Potts model with infinite-range interactions in the external field is analyzed by studying the partition function zeros in the complex field plane. The tricritical point of the three-state model is observed as the approach of the zeros to the real axis at the nonzero field value. Different regimes, involving several first- and second-order transitions of the complicated phase diagram of the three-state model, are identified from the scaling properties of the zeros closest to the real axis. The critical exponents related to the tricritical point and the Yang-Lee edge singularity are well reproduced. Calculations are extended to the negative fields, where the exact implicit expression for the transition line is derived.
authors.affiliation: Department of Physics, Josip Juraj Strossmayer University of Osijek, P.O. Box 125, Trg Ljudevita Gaja 6, 31 000 Osijek, Croatia. zglumac@fizika.unios.hr
authors.forename: Zvonko
authors.initials: Z
authors.lastname: Glumac
authors.forename: Katarina
authors.initials: K
authors.lastname: Uzelac
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D060526:Magnetic Fields; D015233:Models, Statistical