Abstract
The zigzag instability coarsening of splay-bend walls formed in a nematic liquid crystal under external fields is investigated experimentally as a study of one-dimensional analog of spinodal decomposition. When the zigzag instability occurs, a sinusoidal modulation appears firstly. Then the higher harmonics of it progressively grow up as time goes on and the shape of wall changes to zigzag. We have analyzed the time evolution of the sinusoidal modulation in the early stage of coarsening and found that the sinusoidal modulation develops exponentially up to an equilibrium value as expected in the theory of spinodal decomposition.
