Equilibrium and Off-Equilibrium Simulations of Chiral-Glass Order in Three-Dimensional Heisenberg Spin Glasses

Abstract

Spin-glass and chiral-glass orderings in three-dimensional Heisenberg spin glasses are studied both by equilibrium and off-equilibrium Monte Carlo simulations. Fully isotropic model is found to exhibit a finite-temperature chiral-glass transition without the conventional spin-glass order. Although chirality is an Ising-like quantity from symmetry, universality class of the chiral-glass transition appears to be different from that of the standard Ising spin glass. In the off-equilibrium simulation, while the spin autocorrelation exhibits only an interrupted aging, the chirality autocorrelation persists to exhibit a pronounced aging effect reminiscent of the one observed in the mean-field model. Effects of random magnetic anisotropy is also studied by the off-equilibrium simulation, in which asymptotic mixing of the spin and the chirality is observed.