Electrically driven formation and dynamics of Pac-Man solitons in smectic A liquid crystals

Electric field driven instabilities of liquid crystals, such as electro-convections, spatiotemporal chaos, backflows, and solitons are of great importance for both fundamental science and practical applications. Here we demonstrate that...

Effects of surface and shear forces on nano-confined smectic-A liquid crystals studied by X-ray diffraction

The orientational behavior of a smectic-A liquid crystal (4-cyano-4′-octylbiphenyl, 8CB) confined between mica surfaces as well as between silica surfaces with a nanometer scale thickness was investigated by synchrotron X-ray diffraction measurement.

Existence of weak solutions to a dynamic model for smectic-A liquid crystals under undulations

A nonlinear model due to Soddemann et al. (2004, Shear-induced undulation of smectic-A: molecular dynamics simulations vs. analytical theory. Eur. Phys. J. E., 13, 141–151) and Stewart(2007, Dynamic theory for smectic-A liquid crystals. Contin. Mech. Thermodyn., 18, 343–360) describing incompressible smectic-A liquid crystals under flow is studied. In comparison to previously considered models, this particular model takes into account possible undulations of the layers away from equilibrium, which has been observed in experiments. The emerging decoupling of the director and the layer normal is incorporated by an additional evolution equation for the director. Global existence of weak solutions to this model is proved via a Galerkin approximation with eigenfunctions of the associated linear differential operators in the 3D case.

Dynamics of Dislocations in Smectic A Liquid Crystals Doped with Nanoparticles

Edge dislocations are linear defects that locally break the positional order of the layers in smectic A liquid crystals. As in usual solids, these defects play a central role for explaining the plastic properties of the smectic A phase. This work focuses on the dynamical properties of dislocations in bulk samples prepared between two glass plates and in free-standing films. The emphasis will be put on the measurement of the mobility of edge dislocations in liquid crystals either pure or doped with nanoparticles. The experimental results will be compared to the existing models.

Casimir-like interactions and surface anchoring duality in bookshelf geometry of smectic-A liquid crystals

We analyze the transverse intersubstrate Casimir-like force, arising as a result of thermal fluctuations of the liquid crystalline layers of a smectic-A film confined between two planar substrates in a bookshelf geometry, in which the equidistant smectic layers are placed perpendicular to the bounding surfaces.