论文标题
惯性运动的时间尺度在阻尼不足的活动相晶体系统的集体动力学中
Time scales of inertial motion in the collective dynamics of underdamped active phase field crystal systems
论文作者
论文摘要
许多主动物质系统（主要是在微观范围内）被很好地近似为过度阻尼，这意味着任何惯性动量都会立即被环境消散。另一方面，尤其是对于宏观活动系统，而对于许多介观系统，惯性运动的时间尺度可能会变得足够大，以与动力学相关。这就提出了一个问题，即主动物质中的集体动态如何受惯性影响。在本文中，我们实施并研究了阻尼不足的活性相位晶体模型。我们关注集体动力学如何随惯性运动的时间尺度变化。尽管状态图在此修饰中保持不变，但朝向稳定状态的松弛时间尺度大大增加了颗粒质量。我们的数值结果表明，瞬时稳定的密度峰旋转簇充当缺陷，在全球集体运动形式的最终状态之前，需要腐烂。我们定量提取形成时间和衰减时间。最后，我们给出了旋转簇的形成和衰变的物理直觉，以定性地解释提取的时间如何依赖质量。
Many active matter systems, mostly on the microscopic scale, are well approximated as overdamped, meaning that any inertial momentum is immediately dissipated by the environment. On the other hand, especially for macroscopic active systems but also for many mesoscopic ones the time scale of inertial motion can become large enough to be relevant for the dynamics. This raises the question how collective dynamics in active matter is influenced by inertia. In this article we implement and study an underdamped active phase field crystal model. We focus on how the collective dynamics changes with the time scale of inertial motion. While the state diagram stays unaltered in this modification, the relaxation time scale towards the steady state considerably increases with particle mass. Our numerical results suggest that transiently stable rotating clusters of density peaks act as defects which need to decay before the final state of global collective motion forms. We extract the formation and decay times quantitatively. Finally, we give a physical intuition for the formation and decay of rotating clusters to qualitatively explain how the extracted times depend on mass.
