Majumdar Apala, Ockendon John, Howell Peter, Surovyatkina Elena
Department of Mathematical Sciences, University of Bath, Bath BA2 7AY, United Kingdom.
Phys Rev E Stat Nonlin Soft Matter Phys. 2013 Aug;88(2):022501. doi: 10.1103/PhysRevE.88.022501. Epub 2013 Aug 6.
We obtain estimates for critical nematic liquid crystal (LC) temperatures under the action of a slowly varying temperature-dependent control variable. We show that biaxiality has a negligible effect within our model and that these delay estimates are well described by a purely uniaxial model. The static theory predicts two critical temperatures: the supercooling temperature below which the isotropic phase loses stability and the superheating temperature above which the ordered nematic states do not exist. In contrast to the static problem, the isotropic phase exhibits a memory effect below the supercooling temperature in the dynamic framework. This delayed loss of stability is independent of the rate of change of temperature and depends purely on the initial value of the temperature. We also show how our results can be used to improve estimates for LC material constants.
我们获得了在缓慢变化的、依赖于温度的控制变量作用下，向列型液晶（LC）临界温度的估计值。我们表明，在我们的模型中，双轴性的影响可忽略不计，并且这些延迟估计值可以用纯单轴模型很好地描述。静态理论预测了两个临界温度：低于该温度时，各向同性相失去稳定性的过冷温度，以及高于该温度时，有序向列相不存在的过热温度。与静态问题不同，在动态框架下，各向同性相在过冷温度以下表现出记忆效应。这种稳定性的延迟丧失与温度变化率无关，纯粹取决于温度的初始值。我们还展示了如何利用我们的结果来改进对液晶材料常数的估计。
