The field induced stripe texture in surface stabilized ferroelectric liquid crystal cells

Abstract

We investigate the texture which appears as parallel stripes perpendicular to the smectic layers in SSFLC cells. When the temperature approaches the smectic A to smectic C* transition from above in the smectic A phase, a DC field induces the chevron structure due to the electroclinic effect and then the stripe texture is formed. We have identified the stripes to be parallel zig-zag walls. We show that a reasonably high DC voltage changes the structure of the cell from chevron to book-shelf in the smectic C* phase and we show how this happens. We have experimentally found that the width of the stripes is approximately equal to the thickness of the cell and we present a theoretical explanation of the equivalence. We have measured the layer tilt angles in the plane of the cell as a function of temperature and have found them to be the same as the chevron tilt angles determined by X-ray scattering. The result confirms the chevron layer structure and stripe texture models and also gives a simple way to measure chevron layer tilt angles.