Physical review. B, Condensed matter
Variational analyses of series expansions of the Potts model
H. H. Chen, Felix Lee, Yi-Chun Kao
Abstract
A linked-cluster type of series expansion of the free energy with a variational parameter is developed to the eighth order for the q-state Potts model. The order parameter and the internal energy are then derived. By analyzing these series expansions, critical temperatures ${\mathit{T}}_{\mathit{c}}$, latent heats, and discontinuities of the order parameters at ${\mathit{T}}_{\mathit{c}}$ are determined for the cubic lattices.