Tuning the defect configurations in nematic and smectic liquid crystalline shells
Artikel i vetenskaplig tidskrift, 2013

Thin liquid crystalline shells surrounding and surrounded by aqueous phases can be conveniently produced using a nested capillary microfluidic system, as was first demonstrated by Fernandez-Nieves et al. in 2007. By choosing particular combinations of stabilizers in the internal and external phases, different types of alignment, uniform or hybrid, can be ensured within the shell. Here, we investigate shells in the nematic and smectic phases under varying boundary conditions, focusing in particular on textural transformations during phase transitions, on the interaction between topological defects in the director field and inclusions in the liquid crystal (LC), and on the possibility to relocate defects within the shell by rotating the shell in the gravitational field. We demonstrate that inclusions in a shell can seed defects that cannot form in a pristine shell, adding a further means of tuning the defect configuration, and that shells in which the internal aqueous phase is not density matched with the LC will gently rearrange the internal structure upon a rotation that changes the influence of gravity. Because the defects can act as anchor points for added linker molecules, allowing self-assembly of adjacent shells, the various arrangements of defects developing in these shells and the possibility of tuning the result by modifying boundary conditions, LC phase, thickness and diameter of the shell or applying external forces make this new LC configuration very attractive.

microfluidics

self-assembly

emulsions

geometries

colloids

phase

bandgap

colloids

tubules

liquid crystals

order

Författare

H. L. Liang

Martin-Luther-Universität Halle-Wittenberg

Johannes Gutenberg-Universität Mainz

J. Noh

Seoul National University

R. Zentel

Johannes Gutenberg-Universität Mainz

Per Rudquist

Chalmers, Mikroteknologi och nanovetenskap (MC2), Elektronikmaterial och system

J. P. F. Lagerwall

Seoul National University

Advanced Institutes of Convergence Technology

Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences

1364-503X (ISSN) 1471-2962 (eISSN)

Vol. 371 1988 20120258

Styrkeområden

Materialvetenskap

Ämneskategorier

Den kondenserade materiens fysik

DOI

10.1098/rsta.2012.0258