Static and dynamic simulation in the classical two-dimensional anisotropic Heisenberg model

Abstract

By using a simulated annealing approach, Monte Carlo and molecular-dynamics techniques we have studied static and dynamic behavior of the classical two-dimensional anisotropic Heisenberg model. We have obtained numerically that the vortex developed in such a model exhibit two different behaviors depending if the value of the anisotropy $\lambda$ lies below or above a critical value ${\lambda }_c$ . The in-plane and out-of-plane correlation functions ($S^{xx}$ and $S^{zz}$) were obtained numerically for $\lambda <{\lambda }_c$ and $\lambda >{\lambda }_c$ . We found that the out-of-plane dynamical correlation function exhibits a central peak for $\lambda >{\lambda }_c$ but not for $\lambda <{\lambda }_c$ at temperatures above $T_{BKT}$ .

7 pages