Hysteresis and Fréedericksz thresholds for twisted states in chiral nematic liquid crystals: Minimum-energy path approach

Abstract We study minimum-energy pathways (MEPs) between the branches of metastable helical structures in chiral nematic liquid crystals (CNLCs) subjected to electric field applied across cell. By performing stability analysis we have found that, for with non-vanishing half-turn number, threshold (critical) voltage Freedericksz transition is an increasing function free twisting wave number. The curves depend on elastic anisotropy and determine zero-field critical number where director out-of-plane fluctuations destabilize CNLC helix. For each MEP passing through a first order saddle point computed energy barrier as difference saddle-point initial at different values field. In our calculations, approximation next step was determined by obtained previous step, dependence exhibit hysteresis. This hysteresis electrically driven configuration planar tilted involving deformations. It turned out contrast second-order transition, this studied how it depends zenithal anchoring strength.