Axially Polar-Ferroelectric Columnar Liquid Crystalline System That Maintains Polarization upon Switching to the Crystalline Phase: Implications for Maintaining Long-Term Polarization Information
Hikaru Takahashi, Michinari Kohri, Keiki Kishikawa
Abstract
Axially polar-ferroelectric columnar liquid crystals (AP-FCLCs) consist of nanosized axially polarized columnar molecular aggregates arranged in parallel, in which their polar directions can be switched by applying an electric field and maintained after removal of the electric field. However, the problem remains that the induced polarity can be disturbed by external stimuli because liquid crystals are fluid. To solve this problem, we planned to realize a smooth phase transition system from an AP-FCLC phase to a crystal phase without disturbing the induced polar structure. Thus, we designed a urea compound with two biphenyl groups and four 2-butyloctyl groups to achieve the system. As a result, we succeeded in realizing an AP-FCLC compound that transitions from the FCLC phase to the crystal phase at room temperature while maintaining the polarization induced in the FCLC phase, which is expected to enable long-term maintenance of polarization information.