Computer simulation of the similar-Helfrich deformation during the transient planar to planar transition in cholesteric liquid crystals

Abstract

The three-dimensional dynamic relaxation process in cholesteric liquid crystals with low thickness to pitch ratio ((sic)2) after switching off an electric field have been numerically investigated both for cells with parallel boundaries and for ones with perpendicular boundaries. For cholesteric liquid crystal cells with different surface alignment conditions, our simulation results show that the mechanism of transition from homeotropic to planar state is entirely different. In a cell with parallel boundary conditions, the transition from homeotropic to planar is in a sequence of homeotropic - transient planar-planar. In a cell with perpendicular boundary conditions, the relaxation from homeotropic to planar is in a different sequence of homeotropic - planar. The similar-Helfrich deformation only occurs during the transient planar - planar transition. Based on our simulation results, we can also show that the relaxation from homeotropic to planar in a cell with perpendicular boundary conditions is faster than that in a cell with parallel boundary conditions.