Berlin 2018 – scientific programme

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 33: Poster Session III

CPP 33.20: Poster

Tuesday, March 13, 2018, 14:00–16:00, Poster C

Defect topologies in chiral liquid crystals confined to spherically symmetric cavities — •Robert Skutnik, Sergej Püschel-Schlotthauer, and Martin Schoen — Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin, Sekr. C7, Straße des 17. Juni 135, Berlin 10623, Germany

Liquid crystals exhibit an orientational long range order whereas the positional order remains short ranged. The orientational order of achiral liquid crystals can be described by global quantities. For instance, the the molecules align with their symmetry axes along the global director n. In chiral liquid crystals the orientational order becomes local and is given by the local directorfield n(r). Particularly, chiral Blue Phases attract the interest of the scientific community because their orientational distribution appears to be isotropic on a macroscopic length scale whereas regular orientational order is found locally. These properties provide an application as tunable photonic devices. This raises the question for the manipulation of blue phases by external fields (i. e., electromagnetic fields or confinement). Here, we focus on the case of a Blue Phase II confined to a spherical cavity. In order to investigate properties of confined Blue Phases, we perform Monte Carlo simulations in the grand canonical ensemble. The chiral liquid crystal is modeled by a modified 12-6 Lennard-Jones potential which has been repeatedly used to model all known chiral phases adequately. Depending on the cavity diameter as well as on the local alignment at the interface we observe a zoo of novel topological disclination networks.