Hefei National Laboratory for Physical Sciences at Microscales, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China.
Chaos. 2013 Mar;23(1):013112. doi: 10.1063/1.4790832.
Identifying nucleation pathway is important for understanding the kinetics of first-order phase transitions in natural systems. In the present work, we study nucleation pathway of the Ising model in homogeneous and heterogeneous networks using the forward flux sampling method, and find that the nucleation processes represent distinct features along pathways for different network topologies. For homogeneous networks, there always exists a dominant nucleating cluster to which relatively small clusters are attached gradually to form the critical nucleus. For heterogeneous ones, many small isolated nucleating clusters emerge at the early stage of the nucleation process, until suddenly they form the critical nucleus through a sharp merging process. Moreover, we also compare the nucleation pathways for different degree-mixing networks. By analyzing the properties of the nucleating clusters along the pathway, we show that the main reason behind the different routes is the heterogeneous character of the underlying networks.
确定成核途径对于理解自然系统中一级相变的动力学非常重要。在本工作中，我们使用正向通量抽样方法研究了均匀和非均匀网络中的伊辛模型的成核途径，并发现不同网络拓扑的成核过程沿着途径呈现出不同的特征。对于均匀网络，总是存在一个主导的成核簇，较小的簇逐渐附着在其上形成临界核。对于非均匀网络，在成核过程的早期会出现许多小的孤立成核簇，直到它们突然通过一个急剧的合并过程形成临界核。此外，我们还比较了不同度混合网络的成核途径。通过分析途径上成核簇的性质，我们表明不同途径的主要原因是基础网络的异质性。
