Complex-Temperature Singularities of Ising Models
نویسنده
چکیده
We report new results on complex-temperature properties of Ising models. These include studies of the s = 1/2 model on triangular, honeycomb, kagomé, 3·12, and 4·8 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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تاریخ انتشار 1995