Application of the parallel multicanonical method to lattice gas condensation

25th IUPAP Conference on Computational Physics

物理学;计算机科学

Zierenberg, Johannes^1 ; Wiedenmann, Micha^1 ; Janke, Wolfhard^1

Institut für Theoretische Physik, Universität Leipzig, Postfach 100 920, D-04009 Leipzig, Germany^1

关键词: Broad temperature ranges;    Critical density;    Droplet form;    Droplet formation;    Multicanonical method;    Nearest neighbors;    Parallel implementations;    Three dimensions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/510/1/012017/pdf
DOI  :  10.1088/1742-6596/510/1/012017

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

We present the speedup from a novel parallel implementation of the multicanonical method on the example of a lattice gas in two and three dimensions. In this approach, all cores perform independent equilibrium runs with identical weights, collecting their sampled histograms after each iteration in order to estimate consecutive weights. The weights are then redistributed to all cores. These steps are repeated until the weights are converged. This procedure benefits from a minimum of communication while distributing the necessary amount of statistics efficiently. Using this method allows us to study a broad temperature range for a variety of large and complex systems. Here, a gas is modeled as particles on the lattice, which interact only with their nearest neighbors. For a fixed density this model is equivalent to the Ising model with fixed magnetization. We compare our results to an analytic prediction for equilibrium droplet formation, confirming that a single macroscopic droplet forms only above a critical density.