标题： 光激活运动，二维片状物在向列相液晶中的几何和限制诱导的光学效应 显示英文标题

标题： Light-Activated Motion, Geometry- and Confinement-Induced Optical Effects of 2D Platelets in a Nematic Liquid Crystal

摘要： 运动性液晶（LC）胶体由于LC的弹性和表面效应对外部刺激的高度敏感性，表现出独特的行为。 然而，很少有研究关注利用LC相变通过向列-各向同性（NI）界面来推动胶体包含物。 我们设计了一个由固态微米级吸光板状物组成的准二维活性系统，这些板状物浸没在热致向列LC中。 在光照存在的情况下，板状物会自我推进，并同时诱导局部的NI相变。 样品的温度、光照强度和限制决定了三种不同的区域：一个二维大区域，在此区域内，板状物-各向同性相泡是静态的，而NI界面保持稳定；一个紧凑的运动-二维区域，在此区域内，NI界面更靠近板状物的轮廓；以及一个运动-三维限制区域，其特征是LC多极配置的出现。 我们进行了连续理论模拟，预测当在三维中限制时，板状物-LC状态是稳定的。 我们在一个本质上远离平衡的环境中进行的研究对于设计简单的合成系统至关重要，这些系统有助于我们理解如何利用液晶的相变来推动胶体包含物并触发可调节的拓扑重新配置，从而产生光子响应。 显示英文摘要

摘要： Motile liquid crystal (LC) colloids show peculiar behavior due to the high sensitivity to external stimuli driven by the LC elastic and surface effects. However, few studies focus on harnessing the LC phase transitions to propel colloidal inclusions by the nematic-isotropic (NI) interface. We engineer a quasi-2D active system consisting of solid micron-sized light-absorbent platelets immersed in a thermotropic nematic LC. The platelets self-propel in the presence of light while self-inducing a localized NI phase transition. The sample's temperature, light intensity, and confinement determine three different regimes: a 2D large regime where the platelet-isotropic phase bubble is static and the NI interface remains stable; a compact motile-2D regime where the NI interface lies closer to the platelet's contour; and a motile-3D-confinement regime characterized by the emergence of multipolar configurations of the LC. We perform continuum-theory simulations that predict stationary platelet-LC states when confined in 3D. Our study in an intrinsically far-from-equilibrium landscape is crucial for designing simple synthetic systems that contribute to our understanding of harnessing liquid crystals' phase transitions to propel colloidal inclusions and trigger tunable topological reconfigurations leading to photonic responses.