arXiv:hep-lat/9306020 · Journal of Physics A Mathematical and General
Monte Carlo study of topological defects in the 3D Heisenberg model
Christian Holm, W Janke
Abstract
We use single-cluster Monte Carlo simulations to study the role of topological defects in the three-dimensional classical Heisenberg model on simple cubic lattices of size up to 80 3 . By applying reweighting techniques to time series generated in the vicinity of the approximate infinite-volume transition point K c , we obtain clear evidence that the temperature derivative of the average defect density d(n)/dT behaves qualitatively like the specific heat, i.e. both observables are finite in the infinite-volume limit. This is in contrast to results by Lau and Dasgupta(1988) who extrapolated a divergent behaviour of d(n)/dT at K c from simulations on lattices of size up to 16 3 . We obtain weak evidence that d(n)/dT scales with the same critical exponent as the specific heat. As a byproduct of our simulations, we obtain a very accurate estimate for the ratio alpha / nu of the specific-heat exponent with the correlation-length exponent from a finite-size scaling analysis of the energy.