Statics and Dynamics of 1D and 2D Colloidal Lattices with Random Pinning

技术摘要：提出的程序是利用模型胶体系统对随机钉钉问题进行的基础性研究。在这个项目中，PI提出应用ii型超导中著名的Campbell穿透深度概念，在胶体物理中建立一个新的实验范式，称为“应力筛选”，用于研究随机钉住问题。提出的实验包括测量模型一维胶体链和二维胶体晶格的坎贝尔长度。该实验将为布拉格玻璃理论模型中提出的随机流形状态的物理实验探索铺平道路。该项目的研究结果将对随机钉住问题和物质布拉格玻璃的新状态有新的启示，因此对超导、凝聚态物理、表面科学和固态力学具有重要的基础意义。该项目将为研究生和本科生提供纳米制造、视频显微镜和新型光学技术方面的高级培训。这些技能将为学生未来在纳米技术为基础的软物质物理学、生物物理学和材料科学等新兴领域的职业生涯做好准备。摘要：本课题以胶体粒子为模型系统，对凝聚态物理中的随机钉住问题进行了基础性研究。随机钉住问题涉及到许多凝聚态系统。例如，在超导中，超导电缆如何承载电流而不耗散是由磁通量线如何被原子杂质钉住来决定的；在纳米生物技术中，DNA如何通过纳米孔，与DNA分子上的电荷如何与纳米孔的粗糙带电表面相互作用有关，这对DNA测序技术很重要。胶体物质系统具有独特的优势，可以使用光学显微镜实时观察每个粒子，并且可以使用数字视频显微镜研究它们的动力学，从而提供对相互作用，热波动和随机无序之间复杂相互作用的无与伦比的见解。该项目将为研究生和本科生提供纳米制造、视频显微镜和新型光学技术方面的高级培训。这些技能将为学生未来在纳米技术为基础的软物质物理学、生物物理学和材料科学等新兴领域的职业生涯做好准备。

Technical Abstract: The proposed program is a fundamental study of the random pinning problem using model colloidal systems. In this program, the PI proposes to apply the well-known concept of Campbell penetration depth in type-II superconductivity to establish a new experimental paradigm in colloid physics, called "stress screening", in studying the random pinning problem. The proposed experiments include measurements of Campbell length in a model 1D colloidal chains and 2D colloidal lattices. The experiments will pave the way for the experimental exploration of the physics of random-manifold regime proposed in the theoretical models of Bragg glass. The results of this program will shed new light to the random pinning problem and the new state of matter Bragg glass, thus will be of fundamental importance for superconductivity, condensed matter physics, surface science, and solid-state mechanics. This project will provide advanced training for graduate and undergraduate students in nanofabrication, video microscopy, and novel optical technique. These skills will prepare students for their future careers in the emerging areas of nanotechnology-based soft matter physics, biophysics, and materials sciences. Non-Technical Abstract: The proposed program is a fundamental study of the random pinning problem in condensed matter physics using colloidal particles as a model system. The random pinning problem is related to many condensed matter systems. For example, in superconductivity, how a superconducting cable carrying electric current without dissipation is determined by how the magnetic flux lines are pinned by atomic impurities; in nanobiotechnology, how a DNA is driven through a nanopore, important for a DNA sequencing technology, is related to how the charges on a DNA molecule interact with the rough charged surface of the nanopore. The colloidal matter system has the distinct advantage that each particle can be observed in real time using optical microscope and their dynamics can be studied using digital video microscopy, thereby providing unparallel insight into the intricate interplay between interactions, thermal fluctuations and random disorder. This project will provide advanced training for graduate and undergraduate students in nanofabrication, video microscopy, and novel optical technique. These skills will prepare students for their future careers in the emerging areas of nanotechnology-based soft matter physics, biophysics, and materials sciences.