Domain reorientation due to smectic layer instability in high tilt angle-based surface stabilized ferroelectric liquid crystal cell

Abstract

High tilt angle (45°) ferroelectric liquid crystal (FLC) in surface stabilized geometry, having no chiral smectic A (SmA∗) phase, has been studied for the reorientation of the smectic layers near the transition temperature (Tc). The electro-optical studies have shown the stripe domain formation in which the liquid crystal molecules are aligned along the rubbing direction, but the smectic layers are tilted away from the rubbing direction at room temperature. In such high tilt angle FLCs, the molecular alignment and smectic layer formation start from bottom and top rubbed grooves at Tc. The domain formation of the FLC takes place in the middle of the top and bottom surfaces due to the frustration of the dipolar interaction. The smectic layer switching is observed by optical microscopy and confirmed by the dielectric spectroscopy method near Tc of SmC∗ and chiral nematic phases. Domain switching has shown a larger switching angle than the molecular tilt angle within the smectic layer. These studies are expected to be significant for understanding the smectic layer structure and the domain switching process, which may pave the way for large optical switching devices.