Fig. 2: Topologically stable 360o W-pairs of DWs.
From: Soliton walls paired by polar surface interactions in a ferroelectric nematic liquid crystal
a Textures observed between crossed polarizers with P ↓↓ R in the narrow central domain separated by two bright 180o DWs from the wide domains with P ↑↓ R at the periphery; the electric field realigns P in the narrow or wide domains, depending on the field polarity. b The same textures, observed with an optical compensator that allows one to establish the reorientation direction of P. c Topologically nontrivial structure of the 360o W-pair of DWs; along the line γ, the polarization vector P rotates by 360o, thus covering the order parameter space S1 once, which yields the topological charge Q = 1. Cell thickness d = 4.7 µm.
