School of Physics, University of Hyderabad, Hyderabad, India.
Soft Matter. 2016 Aug 10;12(32):6812-6. doi: 10.1039/c6sm01244b.
We report experimental studies on 2D colloidal crystals of dimers stabilized by vortex-like defects in planar nematic and π/2 twisted nematic cells. The dimers are prepared and self-assembled using a laser tweezer. We study the effect of temperature and electric field on the lattice parameters of the colloidal crystals. The lattice parameters vary with the temperature in the nematic phase and a discontinuous structural change is observed at the nematic to smectic-A phase transition. In the nematic phase, we observed a large change in the lattice parameters (≃30%) by applying an external electric field perpendicular to the plane of the 2D crystals. The idea and the active control of the lattice parameters could be useful for designing tunable colloidal crystals.
我们报告了在平面向列相和π/2 扭曲向列相盒中通过旋涡状缺陷稳定的二维胶体晶体的实验研究。使用激光镊子制备和自组装二聚体。我们研究了温度和电场对胶体晶体晶格参数的影响。晶格参数在向列相随温度变化，在向列相到近晶-A 相转变时观察到不连续的结构变化。在向列相中，我们通过施加垂直于二维晶体平面的外部电场观察到晶格参数的大变化（≈30%）。这种晶格参数的设计思想和主动控制可能对可调谐胶体晶体的设计有用。
