We simulate a model of self-propelled disks with soft repulsive interactions confined to a box in two dimensions. For small rotational diffusion rates, monodisperse disks spontaneously accumulate at the walls. At low densities, interaction forces between particles are strongly inhomogeneous, and a simple model predicts how these inhomogeneities alter the equation of state. At higher densities, collective effects become important. We observe signatures of a jamming transition at a packing fraction $ϕ\sim 0.88$, which is also the jamming point for non-active athermal monodisperse disks. At this $ϕ$, the system develops a critical finite active speed necessary for wall aggregation. At packing fractions above $ϕ\sim 0.6$, the pressure decreases with increasing density, suggesting that strong interactions between particles are affecting the equation of state well below the jamming transition. A mixture of bidisperse disks segregates in the absence of any adhesion, identifying a new mechanism that could contribute to cell sorting in embryonic development.
Applications of the kinetic theory for a model of a confined quasi-two dimensional granular mixture: Stability analysis and thermal diffusion segregation
Competing interactions in two dimensional Coulomb systems: Surface charge heterogeneities in co-assembled cationic-anionic incompatible mixtures
限制在平面上的带相反电荷的组分的二元混合物，例如阳离子和阴离子脂质双层，可能表现出局部分离。有利于宏观偏析的净短程相互作用和有利于混合的长程静电相互作用的相对强度决定了有限尺寸或微相偏析的长度尺度。系统的自由能可以在两个不同的区域中进行分析，当考虑高温下的小密度波动时，以及当考虑低温下系统的周期性有序时（F。J. Solis和M. Olvera de la Cruz，J.Chem.Phys.122，054905（2000））。用简单的分子动力学模拟研究了在不同的短程和长程相互作用强度下，带相反电荷的单体与短程Lennard-Jones势相互作用并被限制在二维平面内的情况.该系统具有良好的定义域，其特征在于它们的周期性的长度尺度以及它们的界面的取向排序。通过添加盐，有序的域消失，宏观上的混合物相分离与分析预测一致。
Transport properties in a model of confined granular mixtures at moderate densities
Universidad de Extremadura（埃斯特雷马杜拉大学）；Departamento de Física and Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura（埃斯特雷马杜拉大学物理系与先进计算科学研究所）
Analytical modeling of micelle growth. 3. Electrostatic free energy of ionic wormlike micelles -- effects of activity coefficients and spatially confined electric double layers
Scaling and Condensation of Dry Active Matter Around Circular Obstacles
Faculdade de Física, Universidade Federal do Pará（帕拉联邦大学物理学院）；MMML Lab, Department of Physics, University of Latvia（拉脱维亚大学物理系）；Departamento de Física, Universidade Federal do Ceará（塞阿拉联邦大学物理系）
