Electrooptic and dielectric properties of new antiferroelectric liquid crystal mixtures

Two new antiferroelectric liquid crystal mixtures based on optically active hydroxyesters have been studied with respect to their electro-optic and di electric behavior. The mixtures exhibit only a SmA* phase above SmCa* and s how a stable antiferroelectric order over a broad temperature range (approx imate to 100 degrees C). Electro-optic as well as dielectric studies sugges t that the SmCa*-SmA* transition is second order. In thin cells signs of a surface-induced SmC* phase has also been observed. We present the relevant characteristics for three different electro-optic modes which could be expl oited in these materials, including the very fast linear mode for sub-thres hold voltages.