Phase separation and dynamic pattern formation in heterogeneous self-propelled particle systems
Department of Bioengineering, Binghamton University, SUNY
Last modified: May 31, 2007
The dynamics of self-propelled particle systems have recently been energetically investigated in physics and theoretical biology communities because of their useful implications for the understanding of collective behavior of various autonomous agents, such as bacteria, animals, and pedestrians. Earlier studies focused, with almost no exception, on uniform particle systems, with the assumption that the same set of basic kinetic properties is shared by all the particles within a system. Here we study, through extensive computer simulations, the dynamics of mixtures of multiple different types of self-propelled particles. Our results show that heterogeneous self-propelled particle systems generally undergo spontaneous phase separation, often leading to the formation of multilayer structures. Driven by their own endogenous forces, however, the aggregates of particles may additionally show more dynamic macroscopic behaviors, including oscillation, rotation, and linear or even chaotic motion. The variety of possible dynamics and their dependence on several key kinetic parameters will be discussed.