Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA.
J Chem Phys. 2018 Apr 21;148(15):154902. doi: 10.1063/1.5023403.
Off-lattice active Brownian particles form clusters and undergo phase separation even in the absence of attractions or velocity-alignment mechanisms. Arguments that explain this phenomenon appeal only to the ability of particles to move persistently in a direction that fluctuates, but existing lattice models of hard particles that account for this behavior do not exhibit phase separation. Here we present a lattice model of active matter that exhibits motility-induced phase separation in the absence of velocity alignment. Using direct and rare-event sampling of dynamical trajectories, we show that clustering and phase separation are accompanied by pronounced fluctuations of static and dynamic order parameters. This model provides a complement to off-lattice models for the study of motility-induced phase separation.
无格子活性布朗粒子即使在没有吸引力或速度对准机制的情况下也会形成聚集体并发生相分离。解释这一现象的论点仅诉诸于粒子在波动方向上持续移动的能力，但现有的硬粒子格子模型并不能解释这种行为。在这里，我们提出了一个活性物质的格子模型，该模型在没有速度对准的情况下表现出由运动性诱导的相分离。通过对动态轨迹的直接和稀有事件抽样，我们表明聚类和相分离伴随着静态和动态有序参数的显著波动。该模型为研究由运动性诱导的相分离提供了一个无格子模型的补充。
