Dynamics, Transport, and Ordering of Inclusions in Liquid Crystals

技术摘要*对悬浮在液晶中的包裹体的研究可以为这些材料的粘弹性和界面性质带来重要的新见解，并可以进一步通过流体产生的独特的各向异性相互作用为颗粒的操纵和自组装创造新的平台。此外，颗粒分散的液晶作为具有增强性能的复合材料具有很好的技术前景，这源于颗粒与液晶有序的耦合。这项工作旨在通过研究几类有前途的新系统和粒子相互作用，大大促进我们对液晶中包裹体行为的基本理解和控制。研究的重点包括纳米粒子在近晶液晶中的分散、在微流控阵列中流动的粒子和缺陷向列相以及粒子和离子在液晶中的各向异性输运。该项目的更广泛影响将包括对物理学研究生和本科生的研究、培训和教育，为他们在学术界和工业界的职业生涯做好准备。该项目还将继续并扩大与当地一所科学磁石高中的合作伙伴关系，为巴尔的摩市有才华的学生提供研究实习的机会。*非技术摘要*液晶是由棒状分子组成的流体，其中分子的排列比普通液体中的分子更有序，但比晶体固体中的分子更有序。例子包括向列型液晶和近晶型液晶，在向列型液晶中，分子沿同一方向取向，在近晶型液晶中，分子形成层。当像小颗粒这样的杂质悬浮在这样的流体中时，它可以扰乱这种秩序，导致新的效应，例如颗粒自发地组装成图案，或者颗粒偏离导致它们移动的力。杂质还可以赋予流体增强的材料特性，例如独特的光学和磁性。该项目将对液晶中的几类包裹体进行实验研究，包括纳米级颗粒和携带电流的分子，这些包裹体有望对研究和技术产生潜在的重大影响，但以前很少有人研究这些包裹体。该项目的更广泛影响将包括对物理学研究生和本科生的研究、培训和教育，为他们在学术界和工业界的职业生涯做好准备。该项目还将继续并扩大与当地一所科学磁铁高中的合作伙伴关系，为有才华的巴尔的摩市学生提供研究实习机会。

****Technical Abstract****The study of inclusions suspended in liquid crystals can lead to important new insight about the viscoelastic and interfacial properties of these materials and can further create novel platforms for the manipulation and self-assembly of particles through unique anisotropic interactions engendered by the fluids. In addition, particle-dispersed liquid crystals hold technological promise as composite materials with enhanced properties deriving from the coupling of the particles to the liquid crystalline order. This work aims to advance substantially our fundamental understanding of and control over the behavior of inclusions in liquid crystals by investigating several promising new classes of systems and particle interactions. Among the specific topics on which the research will focus include nanoparticle dispersions in smectic liquid crystals, particle- and defect-laden nematics flowing in microfluidic arrays, and anisotropic transport of particles and ions in liquid crystals. The broader impacts of the project will include research training and education for graduate and undergraduate students in physics that will prepare them for careers in academia and industry. The project will also enable continuation and expansion of a partnership with a local science magnet high school to provide talented Baltimore City students with opportunities for research internships.****Non-Technical Abstract****Liquid crystals are fluids composed of rod-shaped molecules in which the molecules arrange themselves to be more ordered than in an ordinary liquid but less so than in a crystalline solid. Examples include nematic liquid crystals where the molecules orient along a common direction and smectic liquid crystals where the molecules form layers. When an impurity like a small particle is suspended in such a fluid, it can disrupt this order leading to novel effects, such as the spontaneous assembly of the particles into patterns or the deflection of particles away from a force causing them to move. The impurities can also endow the fluids with enhanced material characteristics, such as unique optical and magnetic properties. This project will investigate experimentally several classes of inclusions in liquid crystals, including nanometer-scale particles and molecules that carry electrical current, which promise potentially significant impact on research and technology but which have been the subject of little previous study. The broader impacts of the project will include research training and education for graduate and undergraduate students in physics that will prepare them for careers in academia and industry. The project will also enable continuation and expansion of a partnership with a local science magnet high school to provide talented Baltimore City students with opportunities for research internships.