Visco-elastic modes in some ferroelectric liquid crystals

Abstract

We have studied the Goldstone-mode of three ferroelectric materials near the chiral smectic C (SmC*)-smectic A phase transition. The elastic constants corresponding to the C director in the SmC* phase have been evaluated from the dynamic light scattering measurements. In the material SCE6 we find a slow relaxing mode in addition to the normal Goldstone-mode. This slow relaxation is present only in the SmC* phase and vanishes in the smectic A phase.