Cécile Cottin-B. "Dynamics of Active Particles" Séminaire ESPCI

Dynamics of Active Particles
Cécile Cottin-Bizonne Institut Lumière Matière, Université C. Bernard, Lyon
The behavior of self-propelled particles, that are intrinsically out of equilibrium, is rather fascinating and opens new questions. Here we study experimentally the dynamics of active colloids : from the behavior at low density up to crowded conditions. Our system is a monolayer of micron-size gold-platinum Janus particles in water. Upon addition of hydrogen peroxide, the colloids become self-propelled due to the different chemical gradient on both sides. If at low density they behave as perfect hot gas, at intermediate densities we observe a new phenomena : the formation of clusters. Measuring the aggregation and fragmentation rates we have rationalized the cluster size distribution and fluctuations. In the dense regime, we notice an unexpected non-monotonic behavior as the activity level rises up.
In a second part I will present experimental studies on the dynamics of interfacial swimmers : the spontaneous motion of camphor particles at a liquid-gas interface. Those Marangoni swimmers present complex problems starting with the simplest question of their swimming properties when symmetry breaking arises spontaneously rather than being encoded in the particle properties. I will discuss recent investigations we conducted on the dynamics of lonely camphor swimmer as well as on the original collective dynamics emerging from the interactions between many swimmers.
Egalement dans la rubrique
- L. Botto (séminaire LSIMM)
- C.Y. Hui (Séminaire LSIMM)
- Kenan Song (Séminaire LSIMM)
- Kookheon Char (Séminaire LSIMM) Chaire Total Espci I
- Kookheon Char (Séminaire LSIMM) Chaire Total partie 2
- Bloen Metzger (Séminaire LSIMM)
- Costa S.Patrickios (Séminaire LSIMM)
- Séminaire Catalin R Picu (LISMM)
- H Therien-Aubin (Séminaire LSIMM)
- Marco Ramaioli (Séminaire LSIMM)
- Gaulthier Rydzek (Séminaire LSIMM)
- P.Olmsted (Séminaire LSIMM)
- Julien Dervaux (Séminaire LSIMM)
- N. Baccile (Séminaire LSIMM)
- Oleg Borisof (Séminaire LSIMM)
- Raphael Estevez (Séminaire LSIMM)
- Thierry Chartier (Séminaire LSIMM)
- Shi-Qing Wand (Séminaire LSIMM)
- Tetsuo Yamaguchi (Séminaire LSIMM)
- Le SIMM fabrique des visieres
- Francois Lequeux recompense
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