Two-dimensionalXXZ-Ising model on a square-hexagon lattice

J. S. Valverde, Onofre Rojas, S. M. de Souza
2009 Physical Review E  
We study a two dimensional XXZ-Ising on square-hexagon (4-6) lattice with spin-1/2. The phase diagram of the ground state energy is discussed, shown two different ferrimagnetic states and two type of antiferromagnetic states, beside of a ferromagnetic state. To solve this model, it could be mapped into the eight-vertex model with union jack interaction term. Imposing exact solution condition we find the region where the XXZ-Ising model on 4-6 lattice have exact solutions with one free
more » ... for symmetric eight-vertex model condition. In this sense we explore the properties of the system and analyze the competition of the interaction parameters providing the region where it has an exact solution. However the present model does not satisfy the free fermion condition, unless for a trivial situation. Even so we are able to discuss their critical points region, when the exactly solvable condition is ignored.
doi:10.1103/physreve.79.041101 pmid:19518167 fatcat:zkydmfowjbdjxia6ycghfy7vne