title: Phase transitions of the Ashkin-Teller model including antiferromagnetic interactions on a type of diamond hierarchical lattice.
abstract: Using the real-space renormalization-group transformation, we study the phase transitions of the Ashkin-Teller model including the antiferromagnetic interactions on a type of diamond hierarchical lattices, of which the number of bonds per branch of the generator is odd. The isotropic Ashkin-Teller model and the anisotropic one are, respectively, investigated. We find that the phase diagram, for the isotropic Ashkin-Teller model, consists of five phases, two of which are associated with the partially antiferromagnetic ordering of the system, while the phase diagram, for the anisotropic Ashkin-Teller model, contains 11 phases, six of which are related to the partially antiferromagnetic ordering of the system. The correlation length critical exponents and the crossover exponents are also calculated.
authors.affiliation: Department of Physics and Institute of Theoretical Physics, Beijing Normal University, Beijing 100875, China. jianxinle@yahoo.com
authors.forename: Jian-Xin
authors.initials: JX
authors.lastname: Le
authors.forename: Z R
authors.initials: ZR
authors.lastname: Yang