Smectic Order in Double-Twist Cylinders

TL;DR

This paper introduces a double-twist texture with local smectic order, potentially observed in experiments, and explores its structural properties, dislocation behavior, and the possibility of forming a smectic blue phase.

Contribution

It proposes a new double-twist smectic texture model, analyzing dislocation lattices and geometric constraints, and discusses its relation to smectic blue phases.

Findings

Double-twist textures can be formed with or without melted screw dislocation lattices.

Geometry constrains the angles between smectic regions in the structure.

Connecting double-twist tubes could lead to a smectic blue phase.

Abstract

I propose a double-twist texture with local smectic order, which may have been seen in recent experiments. As in the Renn-Lubensky TGB phase, the smectic order is broken only through a lattice of screw dislocations. A melted lattice of screw dislocations can produce a double-twist texture as can an unmelted lattice. In the latter case I show that geometry only allows for certain angles between smectic regions. I discuss the possibility of connecting these double-twist tubes together to form a smectic blue phase.