MPIDS Colloquium: Onset and control of flows in microtubule-based active nematics
14:15 - 15:15
Prof. Francesc Sagués
Department of Materials Science and Physical Chemistry, Universitat de Barcelona
Max-Planck-Institut für Dynamik und Selbstorganisation (MPIDS)
Prandtl Lecture Hall
Microtubule-based systems are viewed as minimal in vitro reconstitutions of the cytoskeleton. They are made active by mixing them with kinesin proteins fueled with ATP. When this material is two-dimensionally interfaced with oil, it conforms nematic textures pervaded by topological defects and active flows on large length scales.
I will present experimental results corresponding to different scenarios of this active nematic prepa-ration. First, I will introduce recent results relative to the onset dynamics and fully characterization of a turbulent-like regime, identifying the basic length scales and involved instability mechanisms [1, 2]. Later, a strategy of control of these active flows will be commented, based on patterning the vis-cous coupling of the active nematic at the oily interface . Finally, I will refer to situations of ac-tive nematics droplets, dispersed in isotropic and anisotropic oils (liquid crystals) as well . In the latter case, exotic dynamical regimes arising from the coupling of active and passive topological de-fects will be discussed.
 B. Martinez et al., Nature Physics (accepted for publication)
 P. Guillamat et al. Nat. Comm. 8:564, 2017
 P. Guillamat et al., PNAS 114, 5498, 2016
 P. Guillamate et al., Sci. Adv. 4:eeao1470, 2018