Sokolov Andrey, Aranson Igor S, Kessler John O, Goldstein Raymond E
Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2007 Apr 13;98(15):158102. doi: 10.1103/PhysRevLett.98.158102. Epub 2007 Apr 11.
At concentrations near the maximum allowed by steric repulsion, swimming bacteria form a dynamical state exhibiting extended spatiotemporal coherence. The viscous fluid into which locomotive energy of individual microorganisms is transferred also carries interactions that drive the coherence. The concentration dependence of correlations in the collective state is probed here with a novel technique that herds bacteria into condensed populations of adjustable concentration. For the particular thin-film geometry employed, the correlation lengths vary smoothly and monotonically through the transition from individual to collective behavior.
在接近空间排斥允许的最大浓度时，游动的细菌形成一种表现出扩展时空相干性的动态状态。单个微生物的运动能量转移到其中的粘性流体也携带驱动相干性的相互作用。这里用一种新技术探测集体状态下相关性的浓度依赖性，该技术将细菌聚集到浓度可调的凝聚群体中。对于所采用的特定薄膜几何结构，相关长度在从个体行为到集体行为的转变过程中平滑且单调地变化。
