LANGEVIN ALGORITHMS FOR SPIN MODELS

In this paper we investigate order Langevin schemes for simulating lattice spin models. We present a derivation of a second order algorithm and show how it may be combined with Fourier acceleration so as to combat the effects of critical slowing down. We derive explicit results for the case of general SO(N) non-linear sigma models and apply them to the SO(3) model. The strength of the method is that it may be applied to any spin model.