Blume-Emery-Griffiths Model in a Random Transverse Field

TL;DR

This paper investigates how a random quantum transverse field influences the tricritical behavior of the spin-1 Blume-Emery-Griffiths model, revealing dependencies on interaction parameters and disorder concentration.

Contribution

It introduces an effective field theory approach to analyze the impact of disorder on tricritical phenomena in the BEG model.

Findings

Tricritical behavior depends on biquadratic interaction, anisotropy, and disorder concentration.

Existence of a critical disorder probability below which tricritical behavior vanishes.

Disorder can suppress or modify phase transition characteristics.

Abstract

The effect of the random quantum transverse field $\Omega$ 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 $\Delta$, and the concentration $p$ of the disorder of $\Omega$. Indeed, there exist a special value $p_{1}$ of the probability $p$ below which the tricritical behavior disappears.