Topological defects in cholesteric liquid crystal shells.

@article{Darmon2016TopologicalDI,
  title={Topological defects in cholesteric liquid crystal shells.},
  author={Alexandre Darmon and Michael Benzaquen and Simon {\vC}opar and Olivier Dauchot and Teresa Lopez-Leon},
  journal={Soft matter},
  year={2016},
  volume={12 46},
  pages={
          9280-9288
        }
}
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… 
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