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Exact phase diagrams for an Ising model on a two-layer Bethe lattice

Chin-Kun Hu·N. Sh. Izmailian·K. B. Oganesyan
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Abstract

Using an iteration technique, we obtain exact expressions for the free energy and the magnetization of an Ising model on a two - layer Bethe lattice with intralayer coupling constants J1 and J2 for the first and the second layer, respectively, and interlayer coupling constant J3 between the two layers; the Ising spins also couple with external magnetic fields, which are different in the two layers. We obtain exact phase diagrams for the system.

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Chin-Kun Hu, N. Sh. Izmailian, K. B. Oganesyan. 1999-04-01. Exact phase diagrams for an Ising model on a two-layer Bethe lattice. https://doi.org/10.1103/physreve.59.6489

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