主动排斥过程中的阻塞相变
Jamming transition in an active exclusion process
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中文总结 AI 辅助
该研究通过蒙特卡洛模拟和平均场理论，探究一维带方向切换的活性硬核粒子系统的阻塞相变，发现活性会阻碍甚至抑制阻塞形成，临界密度随切换率降低而减小。
中文摘要 AI 辅助
多项关于活性物质的研究表明，活性可诱导或抑制相变，或改变被动系统的临界行为。本文研究活性如何影响阻塞相变——被动系统中非平衡相变的典型范例。我们考虑一维活性粒子系统，粒子具有硬核相互作用和自推进方向，该方向可按给定切换率反转。对于一类粒子跳跃率及无限切换率，我们的模型可简化为被动系统，已知该系统在稳态下呈现高密度流体相与低密度阻塞相之间的转变。通过蒙特卡洛模拟和平均场理论，我们研究粒子的平均迁移率与空穴团簇分布如何随密度和有限切换率变化。主要结果为：活性阻碍阻塞形成，甚至可抑制阻塞；更确切地说，阻塞相变发生在临界密度处，该密度随切换率降低而减小，且在足够小的切换率下，系统仅存在于流体相。
英文摘要
Multiple studies on active matter have shown that activity can induce or suppress a phase transition, or modify the critical behavior of a passive system. Here we investigate how activity affects the jamming transition which is a paradigmatic example of nonequilibrium phase transitions in passive systems. We consider a one-dimensional system of active particles with hardcore interactions and a direction of self-propulsion which can be reversed at a given switching rate. For a class of particle hop rates and infinite switching rate, our model reduces to a passive system which is known to exhibit a transition between a high-density fluid phase and a low-density jammed phase in the stationary state. Using Monte Carlo simulations and a mean field theory, we study how the mean mobility of the particle and the hole cluster distribution vary with density and finite switching rate. Our main result is that activity hinders the formation of jam and can even inhibit it; more precisely, we find that the jamming transition occurs at a critical density that decreases with decreasing switching rate, and at sufficiently small switching rate, the system exists only in the fluid phase.
