The Smectic A to C Phase Transition in Isotropic Disordered Environments

TL;DR

This paper theoretically investigates the smectic A to C phase transition in isotropic disordered environments, revealing that the transition's universality class remains unchanged and is described by the Random Field XY model.

Contribution

It demonstrates that smectic layer fluctuations do not alter the universality class of the transition despite increased fluctuations due to disorder.

Findings

Transition belongs to the Random Field XY universality class

Layer fluctuations do not affect the transition's nature

Disorder enhances fluctuations without changing critical behavior

Abstract

We study theoretically the smectic A to C phase transition in isotropic disordered environments. Surprisingly, we find that, as in the clean smectic A to C phase transition, smectic layer fluctuations do not affect the nature of the transition, in spite of the fact that they are much stronger in the presence of the disorder. As a result, we find that the universality class of the transition is that of the "Random field XY model" (RFXY).