Isotropic, Nematic and Smectic A Phase Behaviour in a Fictitious Field

TL;DR

This paper investigates how external conjugate fields influence the phase diagrams of liquid crystals, revealing multiple topologically distinct behaviors within a mean field framework, especially focusing on a fictitious field's effects.

Contribution

It introduces a mean field model to analyze the impact of conjugate external fields on liquid crystal phase behaviors, highlighting the role of a fictitious field on phase diagram topology.

Findings

External fields induce multiple topological types in phase diagrams.

Fictitious fields significantly alter phase transition characteristics.

The study provides a detailed discussion on the influence of conjugate fields.

Abstract

Phase behaviours of liquid crystals under external fields, conjugate to the nematic order and smectic order, are studied within the framework of mean field approximation developed by McMillan. It is found that phase diagrams, of temperature vs interaction parameter of smectic A order, show several topologically different types caused by the external fields. The influences of the field conjugate to the smectic A phase, which is fictitious field, are precisely discussed.