Turning bacterial suspensions into a "superfluid"

H.M. Lopez, J. Gachelin, C. Douarche, H.Auradou, E. Clément; Phys. Rev. Lett., 115, 28301, (2015)

The rheological response under simple shear of an active suspension of Escherichia coli is determined in a large range of shear rates and concentrations. The effective viscosity and the time scales characterizing the bacterial organization under shear are obtained. In the dilute regime, we bring evidence for a low-shear Newtonian plateau characterized by a shear viscosity decreasing with concentration. In the semidilute regime, for particularly active bacteria, the suspension displays a “superfluidlike” transition where the viscous resistance to shear vanishes, thus showing that, macroscopically, the activity of pusher swimmers organized by shear is able to fully overcome the dissipative effects due to viscous loss.


Top



See also...

Bioinspired turbine blades offer new perspectives for wind energy

V. Cognet, S. Courrech du Pont, I. Dobrev, F. Massouh, B. Thiria; Proc. Roy. Soc. A, 473, (2017) Wind energy is becoming a significant (…) 

> More...

The force of impacting rain

D. Soto, A. Borel De Larivière, X. Boutillon, C. Clanet and D. Quéré, Soft Matter, 2014, 10, 4929. Drop impacts are difficult to characterize due (…) 

> More...

 

Contact

Directeur : Ramiro GODOY DIANA
Codirecteur : Laurent DUCHEMIN
Administratrice : Frédérique AUGER (01 40 79 45 22)
Gestionnaire : Claudette BAREZ (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr
Téléphone : 01 40 79 45 22