Phase Transition of Generalized Ferromagnetic Potts Model - Effect of Invisible States -

TL;DR

This paper studies how adding invisible states to the ferromagnetic Potts model influences the phase transition, revealing that it induces a first-order transition even in two dimensions, with transition properties depending on the number of invisible states.

Contribution

It demonstrates that invisible states cause a first-order phase transition in the Potts model, confirmed through Monte Carlo simulations in two dimensions.

Findings

Invisible states induce first-order transitions.

Transition temperature decreases with more invisible states.

Latent heat increases as invisible states increase.

Abstract

We investigate the nature of the phase transition of the ferromagnetic Potts model with invisible states. The ferromagnetic Potts model with invisible states can be regarded as straightforward extension of the standard ferromagnetic Potts model. The invisible states contribute the entropy, however they do not affect the internal energy. They also do not change the symmetry which breaks at the transition temperature. The invisible states stimulate a first-order phase transition. We confirm that the first-order phase transition with spontaneous $q$-fold symmetry breaking for $q=2,3$, and 4 takes place even on two-dimensional lattice by Monte Carlo simulation. We also find that the transition temperature decreases and the latent heat increases as the number of invisible states increases.