Dynamical and Structural Studies of Liquid Crystal Phases

本研究的目的是研究其结构和动力学 液晶相的行为，使用光学显微镜，光 X射线散射和扫描隧道显微镜。 系统 待探测的液晶膜包括平面的自由悬挂的液晶膜， 在固体基质、液晶之间的互穿制备 局限于气凝胶基质和液晶-固体界面。 该研究旨在阐明表面的影响 和降维对液晶波动、有序性 和相变。 这些研究很重要，因为 它们对凝聚态物理的根本影响， 技术利益。 %%% 本研究的重点是自由悬浮液晶薄膜， 在固体基质、液晶 多孔介质和吸附液体的扫描隧道显微镜 晶体层 该研究旨在阐明 表面和降维对液晶的影响 涨落、有序和相变。 自由悬挂 液晶膜是本领域的基本感兴趣的结构 凝聚态物理学因为它们是已知最薄的稳定的 凝聚相结构，并具有最大的表面积与体积比 任何凝聚相制备的比例。 弱序和 液晶的强界面相互作用使它们成为理想的 研究凝聚态相变物理的材料 多孔介质 这一领域正在成为一个令人兴奋的延伸， 近二十年来的液晶相研究。 超薄 固体基底之间的液晶膜不仅具有宽的 技术兴趣，但他们继续产生各种 有趣的基本物理问题

The goal of this research is to study the structure and dynamical behavior of liquid crystal phases using optical microscopy, light and x-ray scattering, and scanning tunneling microscopy. Systems to be probed include planar freely suspended liquid crystal films, ultrathin preparations between solid substrates, liquid crystals confined to an aerogel matrix, and liquid crystal-solid interface. The research is directed toward elucidating the effects of surfaces and reduced dimensionality on liquid crystal fluctuations, ordering and phase transitions. The proposed studies are important because of their fundamental impact on condensed matter physics and due to technological interests. %%% This research is focused on freely suspended liquid crystal films, ultrathin preparations between solid substrates, liquid crystals in porous media, and scanning tunneling microscopy of adsorbed liquid crystal layers. The research is directed toward elucidating the effects of surfaces and reduced dimensionality on liquid crystal fluctuations, ordering and phase transitions. Freely suspended liquid crystal films are structures of fundamental interest in condensed matter physics because they are the thinnest known stable condensed phase structures and have the largest surface-to-volume ratio of any condensed phase preparation. The weak ordering and strong interface interactions of liquid crystals makes them ideal materials for studying the physics of condensed phase transition in porous media. This area is emerging as an exciting extension of liquid crystal phase research of the past two decades. Ultrathin liquid crystal films between solid substrates are not only of broad technological interest but they continue to generate a variety of interesting basic physics problems.