Switching Dynamics of a Post-Aligned Bistable Nematic Liquid Crystal Device

The operation of a post-aligned bistable nematic (PABN) liquid crystal device is simulated using a dynamic finite-element implementation of the Landau-de Gennes theory in 3D. Two topologically distinct stable director profiles of higher and lower tilt angles are identified. The switching process between these two states is simulated while monitoring the variation in total free energy of the liquid crystal material. Maxima in the free energy, acting as energy barriers separating the two stable states, are shown to coincide with the formation of -1/2 defect lines in the director field.