Work

Topological defects in cholesteric liquid crystal shells

Year: 2016

Type: article

Abstract: We investigate experimentally and numerically the defect configurations emerging when a cholesteric liquid crystal is confined to a spherical shell. We uncover a rich scenario of defect configurations, some of them non-existent in nematic shells, where new types of defects are stabilized by the helical ordering of the liquid crystal. In contrast to nematic shells, here defects are not simple singular points or lines, but have a large structured core. Specifically, we observe five different types of cholesteric shells. We study the statistical distribution of the different types of shells as a function of the two relevant geometrical dimensionless parameters of the system. By playing with these parameters, we are able to induce transitions between different types of shells. These transitions involve interesting topological transformations in which the defects recombine to form new structures. Surprisingly, the defects do not approach each other by taking the shorter distance route (geodesic), but by following intricate paths.

Source: Soft Matter

DOI: 10.1039/c6sm01748g

Authors: Alexandre Darmon, Michael Benzaquen, Simon Čopar, Olivier Dauchot, Teresa Lopez-Leon

Institutions: Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Gulliver, ESPCI Paris, University of Ljubljana

Language: English

Topic: Liquid Crystal Research Advancements

Subfield: Electronic, Optical and Magnetic Materials

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Funder: Agence Nationale de la Recherche

Awards: Liquid crystalline super-atoms, Paris Sciences et Lettres