Hauptseminar Active Matter SS 2017/Clustering of Microswimmers in a Langevin Dynamics Model

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Date

2017-06-20

Time

14:00

Topic

Clustering of Microswimmers in a Langevin Dynamics Model

Speaker

Timur Koyuk

Tutor

Michael Kuron

Contents

By a process called motility-induced phase separation (MIPS), self-propelled particles can spontaneously transition from a dilute suspension to form dense clusters. The properties of these clusters are determined by the particle-particle interactions. Depending on the strength of the active propulsion, phase separation can either be enhanced or inhibited.

To observe these effects in simulation, simple models based on Langevin Dynamics, i.e. without hydrodynamics, are sufficient. This shows that MIPS is a very universal effect. At the same time, it also permits the application of highly efficient Molecular Dynamics (MD) simulations to study systems with millions of particles.

Literature

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  [PDF] (14 MB) [DOI]
• A Suma, G Gonnella, D Marenduzzo, E Orlandini.
  Motility-induced phase separation in an active dumbbell fluid.
  Europhysics Letters 108(5):56004, 2014.
  
• M Cristina Marchetti, Yaouen Fily, Silke Henkes, Adam Patch, David Yllanes.
  Minimal model of active colloids highlights the role of mechanical interactions in controlling the emergent behavior of active matter.
  Current Opinion in Colloid & Interface Science 21:34–43, 2016.
  
• Daan Frenkel, Berend Smit.
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  [DOI]