NIRT: Laser-Guided Assembly of Nanosystems

除非纳米级的结构能够廉价地组装成一个工作系统，否则纳米技术的前景是不会实现的。这项计划的目标是开发和测试一种革命性的工具，使用光压力快速组装复杂的纳米系统，该系统由大小从~10纳米到1毫米的结构组成。智能优点：我们计划开发一种工具，利用光压力逐层组装纳米系统，以产生多个独立的光学陷阱，以便在每一层内同时组织数万个纳米级结构。通过将激光从一个陷阱位置快速扫描到下一个陷阱位置来产生光学陷阱，依靠介质的粘性来稳定位置直到陷阱被刷新，或者通过产生全息图来产生光学陷阱，其中通过使用空间光调制器控制光束的强度和相位分布来同时产生多个光学陷阱。无论采用哪种方式，该工具都必须在逐层组装过程中实时补偿陷阱的散射环境。因此，这项提议的核心有两个要素：1.有效模拟陷阱的动态电磁环境，用于实时预测激光所需的强度和相位分布；2.通过陷阱的自适应光学进行伴随的合成。广泛影响：除了开发一种利用光组装纳米级物体的新工具外，这项工作还有更广泛的影响，来自我们选择探索的试验台的性质，这只能通过光学操纵来制造。特别是，我们计划通过我们在“人造细胞骨架”方面的工作，通过使用光学镊子控制形成细胞结构的分子网络的组装，来帮助理解活细胞的自组装和运动。此外，我们的工作将以一种根本性的方式影响超分子化学，方法是用“光学结合”力增强形成软凝聚物质系统的弱非共价键，如蛋白质、生物膜和DNA。通过将光学结合力与超分子作用力相结合，我们希望能够深入了解超分子聚集体的结构及其相互作用。此外，还计划以每月研讨会、创新的跨学科课程和本科生广泛参与研究的形式进行重大的教育工作。

The promise of nanotechnology won't be realized unless nanometer-scale structures can be assembled together inexpensively into a working system. The goal of this proposal is to develop and test a revolutionary tool that uses light-pressure forces to rapidly assemble complex nanosystems comprised of structures ranging in size from ~10nm to 1mm. Intellectual Merit: We plan to develop a tool to assemble a nanosystem layer-by-layer using light pressure forces to produce multiple, independent optical traps for organizing simultaneously tens of thousands of nanometer-scale structures within each layer. The optical traps will be produced either by rapidly scanning a laser beam from one trap location to the next, relying on the viscosity of the medium to stabilize the position until the trap is refreshed, or by generating a hologram, where multiple optical traps are created simultaneously by controlling the intensity and phase profile of the beam using a spatial light modulator. Either way, the tool will have to compensate in real-time for the scattering environment of the trap during the layer-by-layer assembly. Therefore, there are two elements at the core of this proposal: 1. the efficient simulation of the dynamic electromagnetic environment of the trap, which is used to predict in real-time the required intensity and phase profiles for the laser; and 2. the concomitant synthesis through adaptive optics of the trap.Broader Impact: Aside from the development of a new tool for nanoscale manufacturing that assembles nanometer-scale objects using light, there is a broader impact of this work derived from the nature of the testbeds we choose to explore, which can only be fabricated through optical manipulation. In particular, we plan to contribute to the understanding of self-assembly and locomotion in living cells through our work on "artificial cytoskeletons," by using optical tweezers to control the assembly of the molecular networks that form the cell's structure. Moreover, our work will affect supra-molecular chemistry in a fundamental way by augmenting the weak noncovalent bonds that form soft-condensed matter systems such as proteins, biological membranes and DNA with "optical binding" forces. By using optical binding forces in conjunction with supra-molecular forces, we hope to gain insight into the structure of the supra-molecular aggregates and their interactions. In addition, significant educational efforts are planned in the form of monthly seminars, innovative new interdisciplinary courses, and extensive involvement of undergraduate students in the research.