1995/08/28 by M. Wintel, H. U. Everts, W. Apel · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat
paper · pdf · doi:10.1103/physrevb.52.13480
13 pages, 8 Postscript figures
arxiv created 1995/08/28 · openalex publication_date 1995/11/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have simulated the classical Heisenberg antiferromagnet on a triangular lattice using a local Monte Carlo algorithm. The behavior of the correlation length \ensuremathξ, the susceptibility at the ordering wave vector \ensuremathχ(Q), and the spin stiffness \ensuremathρ clearly reflects the existence of two temperature regimes---a high-temperature regime T\ensuremath\gtrsimTth, in which the disordering effect of vortices is dominant, and a low-temperature regime TTth, where correlations are controlled by small amplitude spin fluctuations. As has previously been shown, in the last regime, the behavior of the above quantities agrees well with the predictions of a renormalization-group treatment of the appropriate nonlinear \ensuremathσ model. For T\ensuremath\gtrsimTth, a satisfactory fit of the data is achieved, if the temperature dependence of \ensuremathξ and \ensuremathχ(Q) is assumed to be of the form predicted by the Kosterlitz-Thouless theory. Surprisingly, the crossover between the two regimes appears to happen in a very narrow temperature interval around Tth\ensuremath≃0.28.