Fig. 4. Preferential placement of colloids with different surface properties in a cell with periodically patterned splay-bend director field.

(A) Polarizing microscope texture of polystyrene colloids with homeotropic and tangential anchoring located in the alternating bands of splay and bend, respectively. (B) Scheme of preferential placement with the experimentally determined director pattern (PolScope observations). The homeotropically anchored spheres reside in the region of splay (y = 0), whereas tangentially anchored spheres localize in the regions of bend (y = ±l/2). Note the different orientations of chains formed by homeotropic spheres (along the x axis) and by the tangential spheres (perpendicular to the x axis). The colloids are placed in an LC mixture with zero dielectric anisotropy. Polarizer is parallel to the x axis and analyzer along the y axis.