标题： 相位排序的动力学与拓扑纹理 显示英文标题

标题： Kinetics of phase ordering with topological textures

摘要： 我们研究了在描述由具有纯耗散动力学的离散非线性O(3) sigma模型的二维系统相序过程中，拓扑纹理和反纹理所起的作用。我们识别并刻画了两种不同的机制来衰减序参量的变化——单个纹理解开和拓扑电荷湮灭。我们的结果显示，在淬火后早期阶段，湮灭过程占主导地位，而在后期阶段，解开过程变得同样重要。我们计算了序参量和拓扑电荷密度的相关性，并表明由于多个长度尺度随时间以不同方式增长，动态缩放被严重违反。 显示英文摘要

摘要： We study the role played by topological textures and antitextures during the phase ordering of a two-dimensional system described by the discretised nonlinear O(3) sigma model with purely dissipative dynamics. We identify and characterise two distinct mechanisms for the decay of the order parameter variations --- single texture unwinding, and topological charge annihilation. Our results show that while at early times after the quench, the annihilation process dominates, the unwinding processes become of comparable importance at later times. We calculate the correlations in the order parameter and in the topological charge density, and show that dynamical scaling is strongly violated due to the occurence of multiple length scales growing differently in time.