Myers Lucas, Swift Carter, Rønning Jonas, Angheluta Luiza, Viñals Jorge
School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA.
Department of Physics, The Ohio State University, Columbus, OH 43210, USA.
Soft Matter. 2024 Mar 27;20(13):2900-2914. doi: 10.1039/d3sm01616a.
A singular potential method in the tensor order parameter representation of a nematic liquid crystal is used to study the equilibrium configuration of a disclination dipole. Unlike the well studied isotropic limit (the so called one constant approximation), we focus on the case of anisotropic Frank elasticity (bend/splay elastic constant contrast). Prior research has established that the singular potential method provides an accurate description of the tensor order parameter profile in the vicinity of a disclination core of a highly anisotropic lyotropic chromonic liquid crystal. This research is extended here to two interacting disclinations forming a dipole configuration. The director angle is shown to decay in the far field inversely with distance to the dipole as is the case in the isotropic limit, but with a different angular dependence. Therefore elastic constant anisotropy modifies the elastic screening between disclinations, with implications for the study of ensembles of defects as seen, for example, in active matter in the extended system limit.
一种用于向列型液晶张量序参量表示的奇异势方法被用于研究位错偶极子的平衡构型。与经过充分研究的各向同性极限（所谓的单常数近似）不同，我们关注各向异性弗兰克弹性（弯曲/伸展弹性常数对比）的情况。先前的研究已经确定，奇异势方法能够准确描述高度各向异性的溶致液晶性液晶位错核心附近的张量序参量分布。本研究在此扩展到形成偶极子构型的两个相互作用的位错。结果表明，指向矢角在远场中与到偶极子的距离成反比衰减，这与各向同性极限情况相同，但角度依赖性不同。因此，弹性常数各向异性改变了位错之间的弹性屏蔽，这对例如在扩展系统极限下的活性物质中所观察到的缺陷集合的研究具有重要意义。
