Emerging Ferroelectric Uniaxial Lamellar (Smectic AF) Fluids for Bistable In-Plane Polarization Memory

作者:Song, Yaohao; Deng, Minghui; Wang, Zhidong; Li, Jinxing; Lei, Huanyu; Wan, Zhe; Xia, Runli; Aya, Satoshi*; Huang, Mingjun*
来源:Journal of Physical Chemistry Letters, 2022, 13(42): 9983-9990.
DOI:10.1021/acs.jpclett.2c02846

摘要

The emerging matter category of liquid-matter ferroelectrics, i.e., ferroelectric nematics, demonstrates an unprecedented combination of fluidity and spontaneous polarization. However, unlike traditional ferroelectrics, the field-switched polarization at zero-field cannot be conserved, so the memory effect remains challenging. Here we report another new type of ferroelectric liquid crystal state, dubbed the ferroelectric smectic A phase, where the polarization is longitudinally coupled to the smectic quasi-layer order. With higher packing density, the phase exhibits higher values of refractive anisotropy and spontaneous polarization compared to the ferroelectric nematics. A delicate balance between the liquid crystal elasticity and flow viscosity enables both the switching and memory of the polarization field, thus opening the door toward realizing liquid-matter ferroelectric memory devices.