CAREER: Electrically- and Optically-Controlled Self-Assembly in Liquid Crystals

Ivan I. Smalyukh，科罗拉多大学博尔德分校物理学助理教授摘要：该项目将在液晶（LC）物理、纳米科学和光子学的界面上进行跨学科研究，重点研究LC复合材料自组装的基础和应用方面。他试图确定分散在LC中间相（从经典的热向列相到由弯曲核分子组成的新相，以及由DNA和活细菌形成的相）中的纳米和微尺寸颗粒自组织背后的组织原理。PI将确定浸没在lc中的纳米和微尺寸粒子周围的导流结构如何依赖于粒子？的形状，尺寸，表面处理，LC中间相的类型，以及应用的外场。他将使用拓扑缺陷，LC蓝相的纳米级周期性缺陷阵列，以及强扭曲的定向结构来进行粒子的空间图像化。信用证吗?S对外部场、表面处理、温度和光的敏感性将使分子和各种形状和化学成分的内含物形成的自组装结构的控制达到前所未有的程度。为了解决这类问题，PI将利用荧光可检测的纳米和微尺寸颗粒（从纳米晶体到活细菌），以便它们在LC样品中的空间定位和排列可以使用荧光共聚焦成像显示。为了深入了解自组装背后的物理现象，光学成像和激光操作将与冷冻断裂透射电子显微镜和同步加速器x射线微束衍射协同结合，从而可以了解从纳米到数十微米长度尺度的分层自组装结构。基本现象将在更广泛的背景下进行研究，从开发基于自组装的可调光学超材料到理解生物膜中细菌-细胞外基质的相互作用。这项工作将推进复杂流体中自组装的知识，并将影响到纳米级相互作用和随后的集体行为、新型显示技术、利用廉价有机太阳能电池将太阳能有效转化为电能、超材料制造和细菌生物膜等领域。PI将把拟议的研究项目纳入广泛的教育和外联活动。非技术概述：PI正在研究纳米颗粒的组织原理和分子自组装成液晶中精确控制的结构。基本的理解？聪明？组装将在细胞和分子水平上揭示生物组织，并将使开发新的电光控制材料成为可能，这些材料具有广角光束转向所需的独特特性，有效地将太阳能转化为电能，以及对社会重要的实用设备，如柔性显示器和数据存储设备。PI将把这项研究纳入教育和推广计划，包括？光、颜色、物质？小学和中学的魔术表演，高中生的科学之旅，为专业协会的学生分会提供建议，为少数民族服务机构的学生和教师提供研究经验，帮助他们确定自己的教育和研究目标，教学？液晶：从基础到应用？参加SPIE访问讲师计划，在全球范围内进行公开讲座，组织国际会议和洲际先进材料与光子学（I-CAMP）暑期学校。I-CAMP暑期学校的讲座将会在网上实时播放，然后转换成网络视频档案和互动教程。此外，这些暑期学校将与面向学生和博士后的拓展论坛和职业发展项目相结合，并将吸引未被充分代表的少数民族参与者。

Proposal 0847782, CAREER: Electrically- & optically-controlled self-assembly in liquid crystals Ivan I. Smalyukh, Asst. Professor of Physics, Univ. of Colorado at BoulderTECHNICAL SUMMARY:The PI will conduct interdisciplinary research at the interfaces of liquid crystal (LC) physics, nanoscience, and photonics, focusing on fundamental and applied aspects of self-assembly in LC composite materials. He seeks to identify the organizing principles behind self-organization of nano- and micro-sized particles dispersed in LC mesophases ranging from the classical thermotropic nematic to the novel phases composed of bent-core molecules, and to those formed by DNA and live bacteria. PI will establish how director structures around nano- and micro-sized particles immersed in LCs depend on particle?s shape, size, surface treatment, type of the LC mesophase, and applied external fields. He will use topological defects, nano-scale periodic defect arrays in LC blue phases, and strongly-distorted director structures for spatial patterning of particles. LC?s sensitivity to external fields, surface treatment, temperature, and light will enable unprecedented degrees of control over formed self-assembled structures of molecules and inclusions of various shapes and chemical composition. In order to engage this class of problems, the PI will utilize fluorescence-detectable nano- and micro-sized particles ranging from nanocrystals to live bacteria, so that their spatial localization and alignment in the LC samples can be revealed using fluorescence confocal imaging. To get insights into the physics phenomena behind the self-assembly, optical imaging and laser manipulation will be combined synergistically with freeze fracture transmission electron microscopy and synchrotron x-ray micro-beam diffraction, so that the hierarchical self-assembly structures from nanometer to tens of microns length scales can be known. The fundamental phenomena will be examined in the broader contexts ranging from development of self-assembly-based tunable optical metamaterials to understanding bacteria-extracellular matrix interactions in biofilms. This work will advance knowledge of self-assembly in complex fluids and will impinge on fields as diverse as nano-scale interactions and ensuing collective behavior, novel display technologies, efficient conversion of solar energy to electricity using inexpensive organic solar cells, metamaterial fabrication, and bacterial biofilms. PI is will integrate the proposed research projects into a broad range of education and outreach activities.NON-TECHNICAL SUMMARY:PI is researching organizing principles of nanoparticle and molecular self-assembly into precisely controlled structures in liquid crystals. Fundamental understanding of this ?smart? assembly will shed light on biological organization at the cellular and molecular levels and will enable development of new electrically- and optically-controlled materials with unique properties needed for wide-angle beam steering, efficient conversion of solar energy into electricity, and for practical devices of importance to society, such as flexible displays and data storage devices. PI will integrate this research into educational and outreach programs, including ?Light, Color, & Matter? Wizard Shows in elementary and secondary schools, Science Tours for high school students, advising student chapters of professional societies, providing research experiences for students and faculty from minority-serving institutions and helping them to define their educational and research goals, teaching ?Liquid Crystals: From Fundamentals to Applications? conference short courses for liquid crystal industry, participating in the SPIE visiting lecturer program by giving public lectures worldwide, and organizing international conferences and inter-continental advanced materials and photonics (I-CAMP) summer schools. Lectures of the I-CAMP summer schools will be webcast in real time and then transformed into web-based video archives and interactive tutorials. Moreover, these summer schools will be integrated with outreach forums and career development programs for students and postdoctoral fellows and will attract underrepresented minority participants.