论文标题
空间变化的底物锚定对不稳定性的影响和薄列液晶膜的脱水
Effects of spatially-varying substrate anchoring on instabilities and dewetting of thin Nematic Liquid Crystal films
论文作者
论文摘要
底物上的部分润湿列液晶（NLC）膜因破坏固体/NLC相互作用力而对脱水型不稳定不稳定。这些不稳定性通过膜的列表来改变，这影响了有效的固体/NLC相互作用。在这项工作中，我们专注于锚定对不稳定性发展的施加底物的影响。该分析是根据NLC膜的Leslie-Ericksen描述在长波公式中进行的。对结果方程的线性稳定性分析表明，不稳定性的某些特征（例如新兴波长）可能不会受到施加的底物锚定的影响。通过大规模GPU模拟考虑的非线性制度进一步进入了非线性制度，但表明非线性效应可能起重要作用，尤其是在强大的基板锚定各向异性的情况下。我们的模拟表明，电影的不稳定在两个阶段发展：第一阶段涉及形成垂直于局部锚定方向的脊。第二个涉及这些脊的破裂和滴的形成，其最终分布受基板施加的各向异性的影响。最后，我们表明，施加更复杂的底物各向异性模式，使我们能够对底物施加的缺陷在导演方向对不稳定性进化中的影响达到基本理解。
Partially wetting nematic liquid crystal (NLC) films on substrates are unstable to dewetting-type instabilities due to destablizing solid/NLC interaction forces. These instabilities are modified by the nematic nature of the films, which influences the effective solid/NLC interaction. In this work, we focus on the influence of imposed substrate anchoring on the instability development. The analysis is carried out within a long-wave formulation based on the Leslie-Ericksen description of NLC films. Linear stability analysis of the resulting equations shows that some features of the instability, such as emerging wavelengths, may not be influenced by the imposed substrate anchoring. Going further into the nonlinear regime, considered via large-scale GPU-based simulations, shows however that nonlinear effects may play an important role, in particular in the case of strong substrate anchoring anisotropy. Our simulations show that instability of the film develops in two stages: the first stage involves formation of ridges that are perpendicular to the local anchoring direction; and the second involves breakup of these ridges and formation of drops, whose final distribution is influenced by the anisotropy imposed by the substrate. Finally, we show that imposing more complex substrate anisotropy patterns allows us to reach basic understanding of the influence of substrate-imposed defects in director orientation on the instability evolution.
