Orientational structures in cholesteric droplets with homeotropic surface anchoring

Soft Matter. 2019 Jul 17;15(28):5554-5561. doi: 10.1039/c9sm00384c.

Abstract

The dependency of orientational structures in cholesteric droplets with homeotropic surface anchoring on the helicity parameter has been studied by experiment and simulations. We have observed a sequence of structures, in which the director configurations and topological defects were identified by comparison of polarized microscopy pictures with simulated textures. A toron-like and low-symmetry intermediate layer-like structures have been revealed and studied in detail. The ranges of stability of the observed structures have been summarized in a general diagram and explained by the helicity parameter dependence of the free energy terms.