论文标题
连接晶体和准晶体的过渡途径
Transition pathways connecting crystals and quasicrystals
论文作者
论文摘要
由于结构性不可约束，从晶体阶段出现了准晶体，这代表了计算物理学的挑战。在这里，使用应用于Landau自由能函数的有效计算方法研究了准晶体的成核。具体而言，通过使用High-Index Saddle Dynamics获得了连接LifShitz-Petrich模型不同局部最小值的过渡途径。这些路径上的鞍点被确定为6倍晶体和12倍准晶体的临界核。结果表明，晶体和准晶相之间的相变可能会遵循两种可能的途径，对应于一个阶段的跃迁和分别涉及可稳态层状准晶体状态的两阶段相变。
Due to structural incommensurability, the emergence of a quasicrystal from a crystalline phase represents a challenge to computational physics. Here the nucleation of quasicrystals is investigated by using an efficient computational method applied to a Landau free-energy functional. Specifically, transition pathways connecting different local minima of the Lifshitz-Petrich model are obtained by using the high-index saddle dynamics. Saddle points on these paths are identified as the critical nuclei of the 6-fold crystals and 12-fold quasicrystals. The results reveal that phase transitions between the crystalline and quasicrystalline phases could follow two possible pathways, corresponding to a one-stage phase transition and a two-stage phase transition involving a metastable lamellar quasicrystalline state, respectively.
