Caprini L, Marini Bettolo Marconi U, Puglisi A
Gran Sasso Science Institute (GSSI), Via. F. Crispi 7, 67100 L'Aquila, Italy.
Scuola di Scienze e Tecnologie, Università di Camerino-via Madonna delle Carceri, 62032 Camerino, Italy.
Phys Rev Lett. 2020 Feb 21;124(7):078001. doi: 10.1103/PhysRevLett.124.078001.
We study a system of purely repulsive spherical self-propelled particles in the minimal setup inducing motility-induced phase separation (MIPS). We show that, even if explicit alignment interactions are absent, a growing order in the velocities of the clustered particles accompanies MIPS. Particles arrange into aligned or vortexlike domains whose size increases as the persistence of the self-propulsion grows, an effect that is quantified studying the spatial correlation function of the velocities. We explain the velocity alignment by unveiling a hidden alignment interaction of the Vicsek-like form, induced by the interplay between steric interactions and self-propulsion.
我们研究了在诱导运动诱导相分离（MIPS）的最小设置下的纯排斥性球形自驱动粒子系统。我们表明，即使不存在明确的排列相互作用，随着MIPS的出现，聚集粒子速度中的有序性也会增加。粒子排列成排列或涡旋状区域，其大小随着自推进持续性的增加而增大，这一效应通过研究速度的空间相关函数进行了量化。我们通过揭示由空间相互作用和自推进之间的相互作用诱导的类似Vicsek形式的隐藏排列相互作用来解释速度排列。
