Statistical Mechanics of Colloidal Particles in Optical Force Fields

* 技术摘要 * 本项目将结合实验观察和理论研究来阐明布朗涡旋的性质，布朗涡旋是一种新发现的随机机器，它使用随机热力将能量转化为运动。传统的确定性机器在冲击波动时会浪费能量，而随机机器则利用随机力来完成热力学循环。 与其他随机机器不同，布朗涡旋在静态力场中演化，该力场结合了联合收割机保守陷阱和非保守驱动力。类似的系统被认为存在于生物化学、社会和金融网络中。 发展布朗涡旋如何工作的基本理解将提供两个研究生的博士论文和四个本科物理专业的荣誉论文。这个实验计划已经促进了第一个实用的牵引光束和第一个打结力场的发展，这两个领域也都有直接的实际应用。我们国家的许多技术都是基于基本机械的组合，如轮子、杠杆和螺钉。 这个项目将阐明一种称为布朗涡旋的新型基本机器的特性，这种机器使用随机热噪声将能量转化为运动。 该计划的基本目标是对布朗涡旋如何工作以及如何在复杂系统中自然出现时识别和表征它们进行深入的物理理解。 该计划将为两名研究生提供博士论文，并为四名本科物理专业学生提供荣誉论文。这些学生将工作的实验利用光学显微操作的最先进技术，其中计算机设计的全息图施加的力和扭矩用于创建和驱动微观机器，以推进基础知识和实际应用。

****Technical Abstract****This project will use a combination of experimental observations and theoretical investigations to elucidate the properties of Brownian vortexes, a newly discovered category of stochastic machines that use random thermal forces to transduce energy into motion. Whereas conventional deterministic machines waste energy punching through fluctuations, stochastic machines instead take advantage of random forces to work through their thermodynamic cycles. Unlike other stochastic machines, Brownian vortexes evolve in static force fields that combine conservative traps and non-conservative driving forces. Analogs of such systems are believed to occur in biochemical, social and financial networks. Developing a fundamental understanding of how Brownian vortexes work will provide doctoral dissertations for two graduate students and honors theses for four undergraduate Physics majors. This experimental program already has fostered the development of the first practical tractor beams and the first knotted force fields, both of which also have immediate real-world applications.****Non-Technical Abstract****Much of our nation's technology is based on combinations of elementary machines, such as wheels, levers and screws. This project will elucidate the properties of a new type of elementary machine called a Brownian vortex that uses random thermal noise to transform energy into motion. The program's fundamental goals are to develop a deep physical understanding of how Brownian vortexes work and how to recognize and characterize them when they arise naturally in complex systems. This program will provide doctoral disserations for two graduate students and honors theses for four undergraduate Physics majors. The experiments on which these students will work take advantage of state-of-the-art techniques of optical micromanipulation, in which the forces and torques exerted by computer-designed holograms are used to create and drive microscopic machines both to advance fundamental knowledge and also for practical applications.