Interlayer-interaction dependence of latent heat in the Heisenberg model on a stacked triangular lattice with competing interactions

Phys Rev E Stat Nonlin Soft Matter Phys. 2013 Nov;88(5):052138. doi: 10.1103/PhysRevE.88.052138. Epub 2013 Nov 26.

Abstract

We study the phase transition behavior of a frustrated Heisenberg model on a stacked triangular lattice by Monte Carlo simulations. The model has three types of interactions: the ferromagnetic nearest-neighbor interaction J(1) and antiferromagnetic third nearest-neighbor interaction J(3) in each triangular layer and the ferromagnetic interlayer interaction J([perpendicular]). Frustration comes from the intralayer interactions J(1) and J(3). We focus on the case that the order parameter space is SO(3)×C(3). We find that the model exhibits a first-order phase transition with breaking of the SO(3) and C(3) symmetries at finite temperature. We also discover that the transition temperature increases but the latent heat decreases as J([perpendicular])/J(1) increases, which is opposite to the behavior observed in typical unfrustrated three-dimensional systems.

Publication types

  • Research Support, Non-U.S. Gov't