Exotic ordered structures of a thin film of a chiral liquid crystal – Jun-ichi Fukuda (Kyushu University)

April 3, 2019 @ 3:10 pm – 3:50 pm
Seminar Room 2
Newton Institute

  Liquid crystals fascinated scientists because they exhibit ordered structures in diverse length scales. Here we focus on structures formed in a thin film of a chiral liquid crystal that allows spontaneous local twist of orientational order. By numerical calculations based on a continuum theory describing the orientational order by a second-rank tensor, we show that a thin film of a chiral liquid crystal exhibit a variety of exotic mesoscale structures depending on temperature, film thickness and surface anchoring that dictates the orientational order at the film surfaces [1,2]. These structures are understood as a result of frustrations between the bulk ordering and the surface anchoring, and include a hexagonal lattice of Skyrmions, vortex-like topological entities that have been shown to emerge in various condensed matter systems. We also briefly mention the optical properties of these structures [2,3].

[1] J. Fukuda and S. Žumer, Phys. Rev. Lett. 104, 017801 (2010); Phys. 
Rev. Lett. 106, 097801 (2011); Nature Commun. 2, 246 (2011).

[2] A. Nych, J. Fukuda, et al., Nature Phys. 13, 1215 (2017).
[3] J. Fukuda et al., Sci.
Rep. 8, 17234 (2018).