A random-field Ising model that is capable of exhibiting a rich variety of multicritical phenomena, as well as a smearing of such behavior, is investigated. The model consists of an infinite-range-interaction Ising ferromagnet in the presence of a triple-Gaussian random magnetic field, which is defined as a superposition of three Gaussian distributions with the same width $\sigma$, centered at H=0 and $H=\pm H_{ 0}$, with probabilities $p$ and $(1-p)/2$, respectively. Such a distribution is very general and recovers as limiting cases, the trimodal, bimodal, and Gaussian probability distributions.
Categories: cond-mat.stat-mech cond-mat.dis-nn