Application of Multicanonical Multigrid Monte Carlo Method to the Two-Dimensional ${\varphi }^4$-Model: Autocorrelations and Interface Tension

Abstract

We discuss the recently proposed multicanonical multigrid Monte Carlo method and apply it to the scalar ${\varphi }^4$-model on a square lattice. To investigate the performance of the new algorithm at the field-driven first-order phase transitions between the two ordered phases we carefully analyze the autocorrelations of the Monte Carlo process. Compared with standard multicanonical simulations a real-time improvement of about one order of magnitude is established. The interface tension between the two ordered phases is extracted from high-statistics histograms of the magnetization applying histogram reweighting techniques.

Comments: 49 pp. Latex incl. 14 figures (Fig.7 not included, sorry) as uuencoded compressed tar file