Dynamic Light Scattering of Ferroelectric Liquid Crystals under an Electric Field

Abstract

We have observed the dynamics of the phase mode (Goldstone mode) in the ferroelectric liquid crystals by the dynamic light scattering method. It is found that the wavenumber dependence of the correlation frequency is of parabolic type with a minimum at the characteristic wavenumber of the helical structure. When a static electric field is applied perpendicular to the helical axis, a correlation frequency gap is induced in the dispersion relation of the phase mode, and the gap increases linearly with the electric field as has been predicted by the phtenomenological thoery.