Martin-Luther University Halle-Wittenberg, Institute of Chemistry-Physical Chemistry, Halle, Germany.
Phys Rev Lett. 2011 Jun 17;106(24):247801. doi: 10.1103/PhysRevLett.106.247801. Epub 2011 Jun 15.
We carry out the first study of smectic liquid crystalline colloidal shells and investigate how their complex internal structure depends on the director configuration in the nematic phase, preceding the smectic phase on cooling. Differences in the free energy cost of director bend and splay give an initial skewed distribution of topological defects in the nematic phase. In the smectic phase, the topological and geometrical constraints of the spherical shell imposed on the developing 1D quasi-long-range order create a conflict that triggers a series of buckling instabilities. Two different characteristic defect patterns arise, one driven by the curvature of the shell, the other by the strong nonuniformities in the director field in the vicinity of the topological defects.
我们进行了第一个关于向列相液晶胶体壳的研究，研究了它们的复杂内部结构如何依赖于冷却过程中进入向列相之前的指向矢配置。指向矢弯曲和倾斜的自由能成本的差异导致了向列相中初始的拓扑缺陷的倾斜分布。在向列相中，球形壳对发展中的一维准长程序施加的拓扑和几何约束产生了冲突，从而引发了一系列的屈曲不稳定性。出现了两种不同的特征缺陷模式，一种是由壳的曲率驱动的，另一种是由拓扑缺陷附近的指向矢场的强烈非均匀性驱动的。
