Preliminary communication Optical investigation of the Goldstone mode in free-standing films of ferroelectric smectic C* phases

An optical method for investigating the dynamics in free-standing films of ferroelectric liquid crystals in the range 10 to 105 Hz by means of optical reflectivity is presented. The experimental results were obtained in the linear-response regime applying electric a. c. fields of strengths less than 16 V cm 1. By measuring the magnitude and phase of the dynamic reflectivity, a relaxation process was found at frequencies near 1 kHz originating from the Goldstone mode.