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Blume-Emery-Griffiths Model in a Random Transverse Field

H. Ez-Zahraouy·H. Mahboub·A. Benyoussef·M. J. Ouazzani
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Abstract

The effect of the random quantum transverse field $Ω$ on the tricritical behavior of the spin-1 Blume- Emery- Griffiths (BEG) model is studied using effective field theory. It is found, that the tricritical behavior depends on both the biquadratic interaction $K$, single- ion anisotropy $Δ$, and the concentration $p$ of the disorder of $Ω$. Indeed, there exist a special value $p_{1}$ of the probability $p$ below which the tricritical behavior disappears.

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H. Ez-Zahraouy, H. Mahboub, A. Benyoussef, M. J. Ouazzani. 2004-11-23. Blume-Emery-Griffiths Model in a Random Transverse Field. https://arxiv.org/abs/cond-mat/0411587

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