Soft Mode Contribution around Sm A-Sm C* Phase Transition Temperature under DC Bias Field in Ferroelectric Liquid Crystal

Abstract
The relaxation of the soft mode is observed both in the Sm A and Sm C* phases by eliminating the contribution of the Goldstone mode under a dc bias field. Three relaxations are observed in the Sm C* phase at the frequency range below 10 MHz. The temperature dependence of the dielectric constant originating in the soft mode shows a sharp peak at the phase transition temperature between the Sm A and Sm C* phases, and shows Curie type behavior. An anomalous dip just below the peak of the dielectric constant is also observed at very high frequencies.