Anomalous yet non-Gaussian diffusion of Passive Tracers in Swarming Bacterial Bath

Yu-Jo Chai^1*, Chien-Jung Lo¹, Yonggun Jun¹

¹Department of Physics, National Central University, Taoyuan 32001, Taiwan

* Presenter:Yu-Jo Chai, email:beanvera752@gmail.com

Diffusion in the active and heterogeneous system is one of the complex phenomena in nature, which shows various properties different from Brownian motion. Here, we present the diffusion of passive tracers in swarming Vibrio alginolyticus bath. With extreme long cell length and negligible hydrodynamic effect, we observe two peculiar features the diffusion of passive tracers in swarming bacterial bath: 1) two anomalous nonlinear scalings in the mean-squared displacement. 2) the non-Gaussian distribution of the particle displacement in time with two scalings. Our observation can be explained by dynamical heterogeneity and strong correlation between particles and bacteria.

Keywords: non-Gaussian diffusion, swarming, diffusing diffusivity, heterogeneity