Hydrogen bonded ferroelectric liquid crystal gels in freely suspended film geometry

Abstract

We study freely suspended films of smectic C* liquid crystalline gels by means of polarizing microscopy. The gel point of the system is determined from the suppression of flow in the films. The network of hydrogen bonds is mechanically fragile but stabilizes orientation patterns of the sample, in particular it stores the texture present during gelation. Electro-optical experiments are performed to study the dynamics of the sample reorientation under the influence of in-plane electric fields. Mesogen orientation and optical properties can be switched in electric fields of a few kV m⁻¹. After removal of electric fields, the network restores the ‘frozen-in’ texture. This texture can be erased by heating the films above the gelation temperature.