Improved Langevin Methods for Spin Systems
  We investigate methods for variance reduction and the elimination of systematic error in a Fourier accelerated Langevin scheme for general spin models. We present results for the $SU(3)\times SU(3)/SU(3)$ model in two-dimensions that are consistent wit h those from multi-grid methods. We argue that the timing for the Langevin method makes it comparable to multi-grid for a given level of error. 
I T Drummond and R R Horgan