Spatial organisation in 3d active matter: from colloids to fish

Add to your list(s) Download to your calendar using vCal

• Paddy Royall (ESPCI ParisTech)
• Tuesday 28 November 2023, 11:00-12:00
• Seminar Room 2, Newton Institute.

If you have a question about this talk, please contact nobody.

SPL - New statistical physics in living matter: non equilibrium states under adaptive control

Fig. 1. Interactions and correlations in Active Matter. (a) Hydrodynamic coupling of Quince Rollerdumbbells to form an excited tetramer state [2,3]. (b) Active labyrinth in self-propelled januscolloids [5]. (c) Zebrafish as a tristable state: schooling, milling and swaming.We present results from three active matter model systems: Quincke Rollers (2d colloids) metaldielectric Janus particles (3d colloids) and zebrafish.In the bulk, Quincke Rollers exhibit an intriguing phase behavior in which two regimes ofmesophase separation similar to passive systems such as diblock copolymers and short rangeattraction-long range repulsion systems are found. At low driving, activity suppresses phaseseparation while at high driving, activity-induced banding leads to mesophase separation [1].Clusters of Quincke Rollers exhibit a hierarchy of novel bound states, reminiscent of excited stateis molecules, only here the coupling is a combination of steric and hydrodynamic interactions [2,3].In passive matter, dimensionality has a profound effect upon phase behaviour. To realise 3d activecolloids, we use metal-dielectric Janus particles, and explore their dynamics and phase behaviour.The latter is somewhat akin to a passive system of dipolar colloids, which forms an array ofpolymorphic colloidal crystal structures. Beyond this already rich and complex behaviour, the activesystem forms novel long-lived structures such as sheets and a labyrinthine phase [5].Finally, we consider zebrafish. These are a convent and well-characterised laboratory based modelsystem. Their bulk behaviour can be mapped onto a modied Vicsek model with surprising accuracy⁶. Now the zebrafish can be tuned, via genetic modification. We find that the Vicsek parametersfor the modified zebrafish can be understood through the physiological change achieved throughthe gene change. Finally, we show that just three zebrafish exhibit a tristable state and aresufficient to capture the many-body behaviour of much larger systems, with only a weak change insystem properties as a function of size.[1] Mauleon-Amieva A, Mosayebi M, Hallett JE, Turci F, Liverpool TB, van Duijneveldt JS and Royall CP,Phys. Rev. E 102 032609 (2020).[2] Mauleon-Amieva A, Allen MP, Liverpool TB and Royall CP, “Dynamics and Interactions of Quincke RollerClusters: from Orbits and Flips to Excited States”, Sci. Adv. 9 eadf5144 (2023).[3] Schwarzendahl FJ, Mauleon-Amieva A, Royall CP, Löwen H, Phys. Rev. E 107 054606 (2023).[4] Mauleon-Amieva A, Liverpool TB, Williams, IP, Souslov, A and Royall CP ArXiV 2311.04288 (2023).[5] Sakaï N and Royall CP, ArXiV 2010.03925 (2020).[6] Yang Y, Turci F, Kague E, Hammond CL, Russo J and Royall CP, PLOS Comp. Biol. 18 e1009394 (2022).   

This talk is part of the Isaac Newton Institute Seminar Series series.

This talk is included in these lists:

• All CMS events
• Featured lists
• INI info aggregator
• Isaac Newton Institute Seminar Series
• School of Physical Sciences
• Seminar Room 2, Newton Institute
• bld31

Note that ex-directory lists are not shown.