4 research outputs found
Elasticity-Dependent Self-assembly of Micro-Templated Chromonic Liquid Crystal Films
We explore micropatterned director structures of aqueous lyotropic chromonic
liquid crystal (LCLC) films created on square lattice cylindrical-micropost
substrates. The structures are manipulated by modulating the LCLC mesophases
and their elastic properties via concentration through drying. Nematic LCLC
films exhibit preferred bistable alignment along the diagonals of the micropost
lattice. Columnar LCLC films, dried from nematics, form two distinct director
and defect configurations: a diagonally aligned director pattern with local
squares of defects, and an off-diagonal configuration with zig-zag defects. The
formation of these states appears to be tied to the relative splay and bend
free energy costs of the initial nematic films. The observed nematic and
columnar configurations are understood numerically using a Landau-de Gennes
free energy model. Among other attributes, the work provide first examples of
quasi-2D micropatterning of LC films in the columnar phase and lyotropic LC
films in general, and it demonstrates alignment and configuration switching of
typically difficult-to-align LCLC films via bulk elastic properties.Comment: 9 pages; 9 figures; accepted for publication in Soft Matte