Fine structures of defect cores induced by elastic anisotropy and biaxiality in hybrid alignment nematics**Project supported by the National Natural Science Foundation of China (Grant Nos. 11374087 and 11447179) and the Key Subject Construction Project of Hebei Province University, China.

Abstract

Based on Landau–de Gennes theory and two-dimensional finite-difference iterative method, the spontaneous distortion in hybrid alignment nematic cells with M = ±1/2 disclination lines is investigated by establishing two models. The fine structures of defect cores are described in the order space S2/Z2. The joint action of elastic anisotropy (L2/L1) and biaxiality of defects induces the spontaneous twist distortion, accompanied by the movement of the defect center to the upper or lower plate. For each model, four mixed defect structures appear with the same energy, which are defined as energetically degenerated quadruple states.