Morphogenesis of liquid crystal topological defects during the nematic-smectic A phase transition

作者：Gim Min Jun; Beller Daniel A; Yoon Dong Ki^*

来源：Nature Communications, 2017, 8(1): 1-9.

DOI：10.1038/ncomms15453

The liquid crystalline phases of matter each possess distinct types of defects that have drawn great interest in areas such as topology, self-assembly and material micropatterning. However, relatively little is known about how defects in one liquid crystalline phase arise from defects or deformations in another phase upon crossing a phase transition. Here, we directly examine defects in the in situ thermal phase transition from nematic to smectic A in hybrid-aligned liquid crystal droplets on water substrates, using experimental, theoretical and numerical analyses. The hybrid-aligned nematic droplet spontaneously generates boojum defects. During cooling, toric focal conic domains arise through a sequence of morphological transformations involving nematic stripes and locally aligned focal conic domains. This simple experiment reveals a surprisingly complex pathway by which very different types of defects may be related across the nematic-smectic A phase transition, and presents new possibilities for controlled deformation and patterning of liquid crystals.

• 出版日期2017-5-30