Observation of Liquid Crystal Fiber Structure in Nematic and Smectic a Phases

A Nematic liquid crystal (LC) fiber (N fiber) and a Smectic A LC fiber (Sm A fiber) were fabricated with Isotropic (I)-(N) and N-Sm A phase transitions using the same sample and by only changing the temperature. LC fibers formed by the self-assembly of LC molecules exhibit optical resonance mode and optical propagation. Therefore, LC fibers are promising for photonic devices. However, the LC fibers reported previously were metastable and unreliable. In previous studies, the Sm A fibers could only be maintained for several tens of minutes. The Sm A fibers fabricated in this study showed stability for more than 2 hours (h). Furthermore, the Sm A fibers showed strong structural stability against external temperature changes. This result provides the possibility of investigating the optical properties of fibers without conventional stabilization techniques.