HIGH-PRECISION SINGLE-CLUSTER MONTE-CARLO MEASUREMENT OF THE CRITICAL EXPONENTS OF THE CLASSICAL 3D HEISENBERG-MODEL

We report measurements of the critical exponents of the classical three-dimensional Heisenberg model on simple cubic lattices of size L3 with L = 12, 16, 20, 24, 32, 40, and 48. The data was obtained from a few long single-cluster Monte Carlo simulations near the phase transition. We compute high precision estimates of the critical coupling K(c), Binder's parameter U*, and the critical exponents nu, beta/nu eta, and alpha/nu, using extensively histogram reweighting and optimization techniques that allow us to keep control over the statistical errors. Measurements of the autocorrelation time show the expected reduction of critical slowing down at the phase transition as compared to local update algorithms. This allows simulations on significantly larger lattices than in previous studies and consequently a better control over systematic errors in finite-size scaling analyses.