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Phase diagram of the spin-1 anisotropic Heisenberg model with a single-ion anisotropy

Jan Dely·Jozef Strecka·Lucia Canova
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Abstract

The spin-1 anisotropic Heisenberg model with a single-ion anisotropy is studied using the Oguchi's pair approximation. Although the theory is developed for lattices with general coordination number, we treat in detail the three-dimensional lattice with the lowest coordination number, i.e. diamond lattice, where the critical and tricritical behavior of the system is analyzed as a function of both the single-ion anisotropy and exchange anisotropy.

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Jan Dely, Jozef Strecka, Lucia Canova. 2007-03-21. Phase diagram of the spin-1 anisotropic Heisenberg model with a single-ion anisotropy. https://arxiv.org/abs/cond-mat/0611212

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