Collaborative Research: CDI-Type II: First-Principles Based Control of Multi-Scale Meta-Material Assembly Processes

胶体纳米或微米颗粒组装成完美有序的周期性结构为制造光子带隙材料和其他具有独特电，磁和光学特性的多尺度超材料提供了基础。 虽然概念验证材料已经在实验室中制造出来，以验证其惊人的特性，但现有的工艺还没有足够的可控性，可扩展性和鲁棒性来进行高通量制造，以实现商业应用。 将胶体组分组装成有序结构的基本限制是热运动、粒子间相互作用和外部场的复杂相互作用，这些相互作用导致缺陷丰富且经常被捕获的状态。 我们提出了一种新的方法来解决元材料组装问题，该方法结合了传统上相互作用最小的四个独立科学领域的专业知识。 胶体系统的数学模型，表示为自由能景观（FEL）在几个关键变量，表征状态的组装过程中，将使用先进的显微成像和分析工具的数据构建。 FEL反过来将被用作严格的过程控制算法的输入，该算法是为随机过程开发的，将导航到无缺陷的产品。这一策略将在原型实验室规模的反应器上进行演示和改进，使用实时数字显微成像作为传感器，可编程粒子-粒子相互作用势&电场作为致动器，以生产超材料。成功开发出大规模组装无缺陷胶体晶体的基本工具，有可能产生革命性的技术（例如，光学计算、能量收集、亚衍射极限成像、隐形衣）与单晶硅的产生类似，以实现集成电路和现代计算。尽管经过了25年的试错努力，但目前还没有一种工艺能够以商业规模生产这种材料。一个严格的实时控制策略，使用定量准确的过程模型，如这里提出的，是必需的。教育和推广活动将整合建模，控制，模拟和实验的概念，包括来自胶体实验的丰富视觉数据（例如图像，视频）和基于物理的模拟（例如渲染，动画），为各级学生提供直观的教育/培训。

The assembly of colloidal nano- or micro-particles into perfectly ordered periodic structures provides a basis for manufacturing photonic band gap materials and other multi-scale meta-materials with unique electric, magnetic, and optical properties. Although proof-of-concept materials have been made in laboratories to verify their amazing properties, no existing process is yet sufficiently controllable, scalable, and robust for high-throughput manufacturing to enable commercial applications. The fundamental limitation to assembling colloidal components into ordered structures is the complex interplay of thermal motion, interparticle interactions, and external fields that lead to defect-rich and often arrested states. We propose a new approach to the meta-material assembly problem that combines expertise from four separate scientific fields that traditionally have had minimal interaction. Mathematical models of the colloidal systems, represented as free energy landscapes (FELs) in a few key variables that characterize the state of the assembly process, will be constructed using data from advanced microscopic imaging and analysis tools. The FELs will in turn be used as input to rigorous process control algorithms, developed for stochastic processes, that will navigate the landscapes to yield defect-free products. This strategy will be demonstrated and refined on prototype lab-scale reactors, using real-time digital microscopic imaging as the sensor and programmable particle-particle interaction potentials & electric fields as the actuators, to produce meta-materials.In terms of broader impact, successful development of fundamental tools for large-scale assembly of defect-free colloidal crystals has the potential to produce revolutionary technologies (e.g. optical computing, energy harvesting, sub-diffraction limit imaging, invisibility cloaking) not unlike the creation of single crystal silicon to enable integrated circuits and modern computing. No existing processes today are capable of producing such materials at a commercial scale despite 25 years of trial-and-error efforts. A strategy of rigorous real-time control using quantitatively accurate process models, like that proposed here, is required. The education and outreach activities will incorporate integrate concepts from modeling, control, simulations, and experiments, including rich visual data from colloid experiments (e.g. images, videos) and physics-based simulations (e.g. renderings, animations) to provide intuitive education/training for students at all levels.