Ferroelectrically Switchable Axial Polarization in Columnar Liquid Crystalline Phases

Recently, ferroelectrically switchable columnar LCs have drawn a great deal of attention for their generation of rich polarization domains. Because of their unique dielectric and self-assembly properties, they are considered to be a promising material for the design of sensors and ultra-high memory devices. Herein, ferroelectrically switchable LCs by using ester, amide, and 1,2,3-triazole groups are reviewed. Most of them do not exhibit genuine ferroelectricity owing to the low energy barrier between the two polar states. The intermolecular interactions between polar groups strongly affect the switchability and stability of polarization. Therefore, it is challenging to balance these two competing factors to improve the ferroelectric function in columnar LCs. Overall, additional effort, including LC design and device fabrication, should be made to optimize the material performance for practical applications in the future.