Breaking planar liquid crystal anchoring to form controllable twist disclination loops

Twist of cholesteric liquid crystal cell with substrates of different anchoring strengths

We consider director configurations of cholesteric liquid crystal (CLC) cells with two plane confining substrates. Exact solutions of the Euler-Lagrange equations for out-of-plane orientations of the easy axes that correspond to inhomogeneous conical structures of CLC director are derived. We study dependence of the CLC twist wavenumber on the free twisting number assuming that anchoring energi...

Generation of vector beams with liquid crystal disclination lines.

We report that light beams, guided along liquid crystal defect lines, can be transformed into vector beams with various polarization profiles. Using finite-difference time-domain numerical solving of Maxwell equations, we confirm that the defect in the orientational order of the liquid crystal induces a defect in the light field with twice the winding number of the liquid crystal defect, coupli...

Model For the Director and Electric Field in Liquid Crystal Cells Having Twist Walls Or Disclination Lines

Two examples of the director structure and electric field in patterned electrode liquid crystal cells are studied using a recently developed calculational model. First, a display cell that exhibits a homeotropic to multidomainlike transition with twist wall structures has been considered for a liquid crystal with positive dielectric anisotropy. The model elucidates the behavior of the electric ...

Sliding planar anchoring and viscous surface torque in a cholesteric liquid crystal.

We propose a surface treatment allowing one to obtain a sliding planar anchoring of nematic (or cholesteric) liquid crystals. It consists of depositing a thin layer of the polymercaptan hardener of an epoxy resin on an isotropic substrate (bare or ITO-coated glass plates). Microscopic observations of defect annihilations and capacitance measurements show that the molecules align parallel to the...

Phase transitions in finite-thickness nematic liquid-crystal films: Planar anchoring.