MMML Laboratory, Department of Physics, University of Latvia, Zeļļu-23, Rīga, LV-1002, Latvia.
Phys Rev E. 2017 Oct;96(4-1):042408. doi: 10.1103/PhysRevE.96.042408. Epub 2017 Oct 13.
Self-organizing behavior has been widely reported in both natural and artificial systems, typically distinguishing between temporal organization (synchronization) and spatial organization (swarming). Swarming has been experimentally observed in systems of magnetotactic bacteria under the action of external magnetic fields. Here we present a model of ensembles of magnetotactic bacteria in which hydrodynamic interactions lead to temporal synchronization in addition to the swarming. After a period of stabilization during which the bacteria form a quasiregular hexagonal lattice structure, the entire swarm begins to rotate in a direction opposite to the direction of the rotation of the magnetic field. We thus illustrate an emergent mechanism of macroscopic motion arising from the synchronized microscopic rotations of hydrodynamically interacting bacteria, reminiscent of the recently proposed concept of swarmalators.
自组织行为在自然和人工系统中都有广泛报道，通常分为时间组织（同步）和空间组织（群集）。在外部磁场的作用下，磁细菌系统中的群集已经在实验中观察到。在这里，我们提出了一个磁细菌集合体的模型，其中流体动力学相互作用除了导致群集之外，还导致时间同步。在稳定化期间，细菌形成准正则六边形晶格结构，整个菌群开始沿与磁场旋转方向相反的方向旋转。因此，我们说明了一种由流体动力学相互作用的细菌微观同步旋转引起的宏观运动的新兴机制，这让人联想到最近提出的群集自动机概念。
