OBSERVATION OF AMPLITUDE MODE UNDER DC ELECTRIC FIELD IN SMECTIC-C * PHASE

OBSERVATION OFAMPLITUDE MODE UNDER DC ELECTRIC FIELD IN SMECTIC-C* PHASE. Linear and nonlinear dielectric spectroscopy under DC electric fields has been performed in the high temperature region of smectic-Cα * phase of an antiferroelectric liquid crystal 4-(1-methyl-heptyloxycarbonyl)phenyl 4-octylcarbonyloxybiphenyl-4-carboxylate (MHPOCBC) to obtain a deeper insight of dynamic properties. It is observed a softening of amplitude mode and ferroelectric mode with increasing the DC field close to the smectic-Cα*-smectic-A(C) phase boundary line. It was seen that the relaxation frequency of the amplitude mode obeys the Curie-Weiss law with respect to the applied electric field