Gessert Denis, Christiansen Henrik, Janke Wolfhard
Institut für Theoretische Physik, Universität Leipzig, IPF 231101, 04081 Leipzig, Germany.
Centre for Fluid and Complex Systems, Coventry University, Coventry, CV1 5FB UK.
Sci Rep. 2023 Aug 15;13(1):13270. doi: 10.1038/s41598-023-39328-7.
One key aspect of coarsening following a quench below the critical temperature is domain growth. For the non-conserved Ising model a power-law growth of domains of like spins with exponent [Formula: see text] is predicted. Including recent work, it was not possible to clearly observe this growth law in the special case of a zero-temperature quench in the three-dimensional model. Instead a slower growth with [Formula: see text] was reported. We attempt to clarify this discrepancy by running large-scale Monte Carlo simulations on simple-cubic lattices with linear lattice sizes up to [Formula: see text] employing an efficient GPU implementation. Indeed, at late times we measure domain sizes compatible with the expected growth law-but surprisingly, at still later times domains even grow superdiffusively, i.e., with [Formula: see text]. We argue that this new problem is possibly caused by sponge-like structures emerging at early times.
在低于临界温度淬火后的粗化过程中，一个关键方面是畴生长。对于非守恒伊辛模型，预测具有相同自旋的畴会以指数为[公式：见原文]的幂律方式生长。综合近期的研究工作，在三维模型零温淬火的特殊情况下，无法清晰观测到这种生长规律。相反，有报道称其生长速度较慢，指数为[公式：见原文]。我们尝试通过在简单立方晶格上进行大规模蒙特卡罗模拟来澄清这一差异，线性晶格尺寸最大可达[公式：见原文]，采用高效的图形处理器（GPU）实现方式。确实，在较晚时间，我们测量到的畴尺寸与预期生长规律相符——但令人惊讶的是，在更晚时间，畴甚至以超扩散方式生长，即指数为[公式：见原文]。我们认为这个新问题可能是由早期出现的海绵状结构导致的。
