Random-anisotropy mixed-spin Ising on a triangular lattice

Abstract

We have studied the mixed spin-1/2 and 1 Ising ferrimagnetic system with a random anisotropy on a triangular lattice with three interpenetrating sublattices A, B, and C. The spins on the sublattices are represented by σ_A (states ±1/2), σ_B (states ±1/2), and S_C (states ±1, 0). We have performed Monte Carlo simulations to obtain the phase diagram temperature (k_B)T/|J| versus the strength of the random anisotropy D/|J|. The phase boundary between two ferrimagnetic FR_1 and FR_2 phases at lower temperatures are always first-order for p < 0.25 and second-order phase transition between the FR_1, FR_2 and the paramagnetic P phases. On the other hand, for values of p ⪆ 0.5, the phase diagram presents only second-order phase transition lines.

Keywords

• random anisotropy
• mixed-spin ising system
• monte carlo simulation