IFIMAC+ICMM Joint Seminar Series focuses on cutting-edge research on condensed matter physics, bringing European speakers to our Cantoblanco Campus, this year via Zoom. You need to be subscribed to our mailing list at the link provided below to get the links to the seminar room. https://listas-correo.uam.es/sympa/subscribe/seminarios-ifimac-icmm-l

Toroids, Active Nematics and Topological Defects

Alberto Fernandez-Nieves

Department of Condensed Matter Physics, University of Barcelona

ICREA – Institució Catalana de Recerca i Estudis Avançats, Barcelona

We will discuss recent results with active nematics confined to either toroidal space. We will first review how we make and stabilize non-spherical droplets and describe how curvature affects defect arrangement on tori. We will show that despite the intrinsic activity and out-of-equilibrium character of the system, there are still remnants of the expected curvature-induced defect unbinding predicted for nematics in their ground state. Activity, however, augments the behavior leading to unexpected defect distributions. We will then focus on defect orientation and show that on flat space, there is short-range orientational correlations without long-range orientational order.