Zeros of the Partition Function for Higher--Spin 2D Ising Models

Victor Matveev; Robert Shrock

doi:10.1088/0305-4470/28/21/004

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Zeros of the Partition Function for Higher--Spin 2D Ising Models

Victor Matveev·Robert Shrock

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Abstract

We present calculations of the complex-temperature zeros of the partition functions for 2D Ising models on the square lattice with spin $s=1$, 3/2, and 2. These give insight into complex-temperature phase diagrams of these models in the thermodynamic limit. Support is adduced for a conjecture that all divergences of the magnetisation occur at endpoints of arcs of zeros protruding into the FM phase. We conjecture that there are $4[s^2]-2$ such arcs for $s \ge 1$, where $[x]$ denotes the integral part of $x$.

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BibTeX RIS

Victor Matveev, Robert Shrock. 1995-05-09. Zeros of the Partition Function for Higher--Spin 2D Ising Models. https://doi.org/10.1088/0305-4470%2F28%2F21%2F004

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