Optical domain switching

Both tilt domains in the green stripe texture switch to the same ferroelectric state in this process, thus causing the stripes to disappear. The anticlinic structure is SmA-like in the sense that the average optic axis is along the layer... 

A second type of behavior existing in the PLZT s is the linear (Pockels) effect which is generally found in high coercive field, tetragonal materials (composition 3), This effect is so named because of the linear relationship between An and electric field. The truly linear, nonhysteretic character of this effect has been found to be intrinsic to the material and not due to domain reorientation processes which occur in the quadratic and memory materials. The linear materials possess permanent remanent polarization however, in this case the material is switched to its saturation remanence, and it remains in that state. Optical information is extracted from the ceramic by the action of an electric field which causes linear changes in the birefringence, but in no case is there polarization reversal in the material. 

A conglomerate in real liquid crystalline phases was first observed in the smectic phase of a rod-shaped mesogen with two stereogenic centers in its tail [42], We used a racemic mixture which was supposed not to electrically switch. Evidence for conglomerate formation was provided by clear electro-optic switching and texture observation under a polarizing microscope domains with stripes, which themselves display fine stripes. These stripes are tilted in two different directions with respect to the primary stripes. This is a still very rare example now that fluid soft matter is known to resolve spontaneously into a three-dimensional conglomerate. 

Finally, the possibility of pure optical switching has been demonstrated in principle by photoinducing supramolecular helical arrangements of smectic domains in some liquid crystal azo polymer films." The photoinduced chirality is pronounced and stable (our oldest sample is still fairly young), but the process is again slow, because it requires reorientation of whole domains. 

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