Magnetic Tricritical Points in Ising Antiferromagnets

Abstract

The thermodynamic properties of the antiferromagnetic Ising simple cubic and square lattices with nearest-neighbor and next-nearest-neighbor interactions have been studied using a Monte Carlo technique. Although both systems were found to possess magnetic tricritical points, their behavior in the "tricritical region" differed from that found in ${\mathrm{He}}^{3}$-${\mathrm{He}}^{4}$ mixtures.