Raphaël Jeanneret
ENS, Département de physique, LPENS

“Some physics about colloidal active/passive mixtures”

The way single colloidal objects behave in presence of active forces arising from within the bulk of the system is crucial to many situations, notably biological, and potential medical or environmental applications, from the targeted delivery of cargoes to the depollution of waters and soils. After introducing some basic concepts of micro-organismal hydrodynamics, I will present experimental findings that my collaborators and I have obtained over the past 6 years on the dynamics of Brownian colloids in suspensions of biological micro-swimmers, notably the green alga Chlamydomonas reinhardtii. These results will be rationalized using theoretical approaches from hydrodynamics and stochastic processes.