Surface-assisted single-crystal formation of charged colloids
Surface-assisted single-crystal formation of charged colloids
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DOI：
10.1038/nphys4034
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发表时间：
2017-05-01
期刊：
影响因子：
19.6
通讯作者：
Tanaka, Hajime
中科院分区：
文献类型：
--
作者：
Arai, Shunto;Tanaka, Hajime
衬底诱导异质成核是一种在控制晶向的同时形成缺陷较少的扩展单晶的很有前途的方法。然而，尽管它在技术上很重要，但这一过程背后的物理原理仍然难以捉摸。通过实验和数值模拟研究了单粒子水平下晶体形核和生长的动力学过程，揭示了衬底诱导单晶形成的关键是在过冷液体中形成的局部有利结构与最稳定晶体之间的角对称性匹配，以及前者与衬底诱导的液体分层之间的非平凡耦合。这两个条件对于直接形成最稳定的晶体，同时保持其相对于衬底的唯一方向至关重要。我们还讨论了带电系统的特殊特性。我们的发现表明，在衬底的影响下，过冷液体状态下的预有序化在很大程度上主导了未来的结晶过程，为控制非均相结晶提供了新的见解。
Substrate-induced heterogeneous nucleation is a promising way to form an extended single crystal with few defects while controlling its direction. Despite its technological importance, however, the physics behind this process has remained elusive. By studying the kinetic pathway of crystal nucleation and growth at a single-particle level both experimentally and numerically, we reveal that the keys to substrate-induced monomorphic single-crystal formation are matching of the angular symmetry between locally favoured structures formed in a supercooled liquid and the most stable crystal and non-trivial coupling of the former to substrate-induced layering in the liquid. These two conditions are crucial for direct formation of the most stable crystal while keeping its unique direction relative to the substrate. We also discuss special features of charged systems. Our finding indicates that pre-ordering in a supercooled liquid state under the influence of a substrate largely dominates the course of future crystallization, providing new insights into the control of heterogeneous crystallization.