论文标题
具有较大尺寸分散性堵塞颗粒的二元混合物中的相变
Phase transition in the binary mixture of jammed particles with large size dispersity
论文作者
论文摘要
已经有很好的确定，颗粒系统显示了与之相关的干扰过渡和临界缩放行为。但是，我们的知识仅限于（几乎）单分散系统。最近，研究了具有较大尺寸分散剂的二元混合物，并提出出现了两个不同的堵塞相。在这里，我们对该系统进行了彻底的数值研究，特别关注对参与刚性网络的小颗粒的比例的统计数据和有限尺寸的影响。我们提供了有力的证据表明，两个不同的障碍阶段根据两个物种的压力和组成而出现，这些阶段是由一阶相变隔开的。在两个阶段之一中，只有大颗粒被卡住，而在另一阶段都会堵塞小颗粒。我们还描述了压力组合平面中的相图，其中一阶相变线在临界点终止。此外，我们根据相图上的弹性模量研究了机械性能，并发现弹性模量的不连续变化在整个相变中出现。值得注意的是，尽管不连续，但每个堵塞相中的弹性模量与单分散系统中的弹性均具有相同的缩放定律。
It has been well established that particulate systems show the jamming transition and critical scaling behaviors associated with it. However, our knowledge is limited to (nearly) monodisperse systems. Recently, a binary mixture of jammed particles with large size dispersity was studied, and it was suggested that two distinct jammed phases appeared. Here, we conduct a thorough numerical study on this system with a special focus on the statistics of and finite-size effects on the fraction of small particles that participate in the rigid network. We present strong evidence that two distinct jammed phases appear depending on the pressure and composition of two species, which are separated by the first-order phase transition. In one of two phases, only large particles are jammed, whereas both small and large particles are jammed in the other phase. We also describe the phase diagram in the pressure-composition plane, where the first-order phase transition line terminates at a critical point. In addition, we investigate the mechanical properties in terms of the elastic moduli over the phase diagram and find that discontinuous changes in elastic moduli emerge across the phase transition. Remarkably, despite the discontinuities, the elastic moduli in each jammed phase exhibit identical scaling laws to those in the monodisperse systems.
