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Partition Function Zeros of a Restricted Potts Model on Lattice Strips and Effects of Boundary Conditions

Shu-Chiuan Chang·Robert Shrock
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Abstract

We calculate the partition function $Z(G,Q,v)$ of the $Q$-state Potts model exactly for strips of the square and triangular lattices of various widths $L_y$ and arbitrarily great lengths $L_x$, with a variety of boundary conditions, and with $Q$ and $v$ restricted to satisfy conditions corresponding to the ferromagnetic phase transition on the associated two-dimensional lattices. From these calculations, in the limit $L_x \to \infty$, we determine the continuous accumulation loci ${\cal B}$ of the partition function zeros in the $v$ and $Q$ planes. Strips of the honeycomb lattice are also considered. We discuss some general features of these loci.

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Shu-Chiuan Chang, Robert Shrock. 2006-02-18. Partition Function Zeros of a Restricted Potts Model on Lattice Strips and Effects of Boundary Conditions. https://doi.org/10.1088/0305-4470%2F39%2F33%2F002

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