Similarity and Dissimilarity between Influences of Anchoring Walls and of External Fields on Nematic and Smectic A Phases

TL;DR

This paper investigates how anchoring walls and external fields differently influence nematic and smectic A phases in liquid crystals, revealing a critical thickness for phase transitions and contrasting their effects through phase diagrams and order parameters.

Contribution

It provides a comparative analysis of the effects of anchoring walls and external fields on liquid crystalline phases, highlighting the critical thickness and differences in phase behavior.

Findings

Existence of a critical thickness below which no phase transition occurs.

Differences in influence of walls and fields elucidated via order parameters.

Phase diagrams show distinct effects of external fields versus anchoring walls.

Abstract

The McMillan liquid crystalline models under the influence of homeotropic anchoring walls and of external fields are investigated. For thin systems, the existence of the critical thickness, below which the system does not undergo a discrete phase transition, is confirmed. Apparent differences between the influence of the anchoring walls and of external fields are elucidated by investigating the order parameters and a temperature vs external field phase diagram for the bulk systems.