Collective structure and dynamics of colloids far-from equilibrium

Active colloids;Collective dynamics

Zhang, Jie

关键词: Active colloids;    Collective dynamics;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/99461/ZHANG-DISSERTATION-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

One characteristic feature of life is to convert energy from one form to another to perform functions in response to stimuli; based on this essential element, and their convenient size, colloidal particles are designed to mimic life, such as cells, bacteria and even larger animals, in the past decade. With this simplified model system, many aspects of physics of life, such as pattern formation, swarming/flocking behavior and response to heterogeneous environment, can be explored. More importantly, by stepping bravely from the conventional equilibrium framework of thinking, active matter opens a new direction for non-equilibrium physics, relevant or irrelevant to life. Without the simple rule to minimize free energy toward equilibrium, it is challenging to predict theoretically and study experimentally how a system with constantly supplied energy would evolve, especially when interactions between elements lead to dynamic effects resulting in unexpected emergent behavior. Going beyond the traditional scheme of relying on equilibrium statistics and free energy minimization to explain the system behavior, this thesis focuses on the rich structure and dynamics of active colloids, with energy constantly injected to the system at single particle level. From small cluster assembly behavior to large scale emergent phenomena involving hundreds of thousands of the particles, dynamic effects become equally or even more important in determining the structure and maintaining the unsettling dynamics.