Fernández-Nieves A, Vitelli V, Utada A S, Link D R, Márquez M, Nelson D R, Weitz D A
Department of Physics and HSEAS, Harvard University, Cambridge, Massachusetts 02138, USA.
Phys Rev Lett. 2007 Oct 12;99(15):157801. doi: 10.1103/PhysRevLett.99.157801. Epub 2007 Oct 9.
We use double-emulsion drops to experimentally investigate the defect structures of spherical shells of nematic liquid crystals. We uncover a rich scenario of coexisting defect structures dictated by the unavoidable finite thickness of even the thinnest shell and by the thickness variation around the sphere. These structures are characterized by a varying number of disclination lines and pairs of surface point defects on the inner and outer surfaces of the nematic shell. In the limit of very thick shells the defect structure ultimately merges with that of a bulk nematic liquid crystal drop.
我们使用双乳液滴对向列型液晶球壳的缺陷结构进行实验研究。我们发现了由即使是最薄球壳不可避免的有限厚度以及球体周围厚度变化所决定的共存缺陷结构的丰富情形。这些结构的特征是向列型壳体内外表面上的位错线数量以及表面点缺陷对数量各不相同。在非常厚的球壳极限情况下,缺陷结构最终与块状向列型液晶滴的缺陷结构合并。