ELECTROOPTIC SOFT MODE RESPONSE OF COMPOUNDS EXHIBITING THE ANTIFERROELECTRIC PHASE

We report measurements on the electrooptic response of thin samples (s imilar to 2-5 mu m) of two antiferroelectric liquid crystals. All the phase transitions in these compounds can be very easily detected using this technique. We have been able to measure such an electrooptic eff ect for the first time in the antiferroelectric and smectic I phases of a tolane compound. The response shows a relaxation at high frequenc ies (similar to 10 KHz) and is attributed to a soft mode which produce s an asymmetry in the molecular tilt in successive layers.