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.

Haut de page



À lire aussi...

Forbidden directions for the fracture of thin anisotropic sheets : an analogy with the Wulff plot

A. Takei, B. Roman, J. Bico, E. Hamm & F. Melo, Physical Review Letter, 110 144301 (2013) It is often postulated that quasistatic cracks (...) 

> Lire la suite...

Does aquatic foraging impact head shape evolution in snakes ?

M. Segall, R. Cornette, A.-C. Fabre, R. Godoy-Diana, A. Herrel ; Proc. R. Soc. B, 283, 20161645, (2016) Evolutionary trajectories are often (...) 

> Lire la suite...

 

Informations Pratiques

Laboratoire : 01 40 79 45 22
Directeur : Damien Vandembroucq
Codirecteur : Philippe Petitjeans
Administratrice : Frédérique Auger (01 40 79 45 22)
Gestionnaire : Claudette Barez (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr

Nous rendre visite