Critical splay fluctuations and colossal flexoelectric effect above the nonpolar to polar nematic phase transition

Polar and nonpolar orderings in the electrically induced isotropic-nematic phase transition.

We study the dynamics of the isotropic-nematic phase transition caused by an applied electric field at the time scales of dielectric relaxation. In the classic Landau-Khalatnikov theory of the phase transition dynamics, the nematic (nonpolar) order parameter is an instantaneous function of the applied field. We demonstrate that, when the field is changing faster than the time of dielectric rela...

Critical Splay-Bend Deformation of Nematic Films

I n t h i n nemat ic f i lms the d i rec tor field n may on ly depend on z, the n o r m a l to the film p lane. There are two stable conf igurat ions w i t h less than a l l three types of de fo rma t ion present, the pure tw is t and the pure splay-bend. Fo r the pure tw is t under the add i t i ona l in f luence of an ex te rna l field n o r m a l to the tw is t p lane the range of s tab i l ...

A Molecular Theory of the Nematic to Nematic Phase Transition in Strongly Polar Compounds

As described in the previous chapter, the nematic (N) liquid crystal is characterised by a long range orientational order of the long axes of the molecules without a long range positional order of their centres of mass (see section 1.2.1, chapter-1). The preferred axis of orientation in the nematic liquid crystal, called the director, is represented by the unit vector n ^ . The extent of orient...

Threshold Flexoelectric Effect in Nematic Liquid Crystal

Critical behavior at the nematic-to-smectic-A transition in a nonpolar liquid crystal with wide nematic range.