(188c) Self-Assembly of Micro-Rods in Nematic Liquid Crystal Controlled by Boundary Conditions

While the physics of spherical colloids confined in a nematic slab has been thoroughly investigated (see, e.g. [1-3]), interactions between anisotropic particles are less well studied [4-6].  Here, we report the behavior of micro-rods confined in a nematic cell.  The anchoring conditions on the particles and on the bounding walls of the cell are well defined. Depending on the type of anchoring, cylinders spontaneously form 1D structures, chains parallel to the director, and 2D ordered structures, crystals with hexagonal symmetry.  These latter structures are not observed for isotropic particles. By application of an external field, the anchoring conditions on the bounding walls can be dynamically controlled, and transitions between the different structures can be generated. Recent progress in understanding the particle self-assembly process is presented.

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