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arXiv · hep-lat/9509054

Complex-Temperature Singularities of Ising Models

Robert Shrock
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Abstract

We report new results on complex-temperature properties of Ising models. These include studies of the $s=1/2$ model on triangular, honeycomb, kagomé, $3 \cdot 12^2$, and $4 \cdot 8^2$ lattices. We elucidate the complex--$T$ phase diagrams of the higher-spin 2D Ising models, using calculations of partition function zeros. Finally, we investigate the 2D Ising model in an external magnetic field, mapping the complex--$T$ phase diagram and exploring various singularities therein. For the case $βH=iπ/2$, we give exact results on the phase diagram and obtain susceptibility exponents $γ'$ at various singularities from low-temperature series analyses.

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Robert Shrock. 1995-09-15. Complex-Temperature Singularities of Ising Models. https://doi.org/10.1016/0920-5632(96)00161-2

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