Theory of Liquid Crystals and Related Materials

液晶及相关材料理论

• 批准号: 9423114
• 负责人: Tom Lubensky
• 金额: $ 26.4万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-03-01 至 1998-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9423114&HistoricalAwards=false
• 关键词: Theory; Liquid; Crystals; Related; Materials

9423114 Lubensky This project involves theroetical investigations of three subprojects related to liquid crystals: the quasicrystalline twist-grain-boundary C phase, the shape of droplets in Langmuir films, and multiple scattering of light from liquid crystals. The twin-grain-boundary phase has recently been observed experimentally. The PI proposes to study this thoroughly, including the development of a guage theory for the Smectic-C phase that will be used to calculate dislocation energies in type II systems, an analysis of dipolar interactions, and a search for the origins of quasicrystalline lock-in. The possibility that chiral pinwheel droplets of Langmuir which have been observed recently are reproduced by effective anisotropic negative line tension favoring large perimeter and the capture of a topological defect will be investigated. The extension of diffusion-wave spectroscopy formalism to nematic liquid crystals in which multiple scattering in an anisotropic medium is produced by long-range fluctuations in the dielectric constant will be studied. %%% In this project Lubensky will continue his theoretical study of complex fluids, such as liquid crystals. He is considered a world leader in the theory of these materials. The first part involves the investigation of a phase (just recently discovered in experiments) of unique structure and symmetry which may prove to be technologically important. The second part, involving the study the shapes of droplets of molecular films, will help understand interactions within the molecules that make up monolayers, a topic of great interest to both physicists and biologists. The third part, analyzing the application of a relatively new experimental technique to liquid crystals, may provide an important tool for studying liquid crystals. It is worth noting that Lubensky has just finished his collaboration with Chaikin of a new textbook in graduate level condensed matter physics that many believe will replace the textbook currently considered the standard in this area. ***

9423114 Lubensky该项目涉及与液晶相关的三个子项目的理论研究：准晶扭曲晶界C相，朗缪尔薄膜中液滴的形状，以及液晶光的多重散射。 最近在实验上观察到了孪晶晶界相。 PI建议对此进行彻底的研究，包括开发用于计算II型系统中位错能的Smectic-C相的规范理论，分析偶极相互作用，以及寻找准晶锁定的起源。 最近已经观察到的朗缪尔的手性风车液滴的可能性被复制的有效各向异性负的线张力有利于大周长和捕获的拓扑缺陷将被调查。 扩散波光谱形式主义的扩展，在各向异性介质中的多重散射产生的介电常数的长程波动的液晶将被研究。 在这个项目中，Lubensky将继续他对复杂流体（如液晶）的理论研究。 他被认为是这些材料理论的世界领导者。 第一部分涉及到一个阶段（最近在实验中发现）的独特结构和对称性，这可能被证明是技术上重要的调查。 第二部分涉及研究分子膜液滴的形状，将有助于理解构成单层的分子内的相互作用，这是物理学家和生物学家都非常感兴趣的话题。 第三部分，分析了一种相对较新的实验技术在液晶中的应用，可能为研究液晶提供一个重要的工具。 值得注意的是，Lubensky刚刚完成了他与Chaikin的研究生水平凝聚态物理学新教科书的合作，许多人认为这将取代目前被认为是该领域标准的教科书。 ***