Mean-Field Analysis of Antiferromagnetic Three-State Potts Model with Next Nearest Neighbor Interaction

TL;DR

This paper analyzes the phase behavior of a three-state Potts model with competing interactions using mean-field theory, revealing phase transitions and tricritical points.

Contribution

It provides a mean-field analysis of the antiferromagnetic three-state Potts model with next-nearest-neighbor interactions, identifying phase phases and transition types.

Findings

Identifies BSS and PSS ordered phases.

Discontinuous phase transition line separates phases.

Tricritical point where transition nature changes.

Abstract

The three-state Potts model with antiferromagnetic nearest-neighbor (n.n.) and ferromagnetic next-nearest-neighbor (n.n.n) interaction is investigated within a mean-field theory. We find that the phase-diagram contains two kind of ordered phases, so-called BSS phase and PSS phase, separated by a discontinuous phase transition line. Order-disorder transition is continuous for the weak n.n.n. interaction and becomes discontinuous transition when the n.n.n. interaction is increased. We show that the multicritical point where the order-disorder transition becomes discontinuous is indeed a tricritical point.