Soft mode of nematic liquid crystal with positive dielectric anisotropy

Abstract

The isotropic-nematic phase transition is generally a first-order phase transition. Itis theoretically predicted that a critical endpoint appears when an electric field is applied to a nematic liquid crystal with a positive dielectric anisotropy. We have reported that the soft mode can be observed by performing permittivity measurements under a DC electric field. In this study, we attempted to clarify the soft mode behavior from the permittivity measurement using the method proposed in our previous research. As a result, it was clarified that when an electric field of a certain magnitude or more is applied, a peak due to the soft mode appears in the temperature dependence of the permittivity.