Nanoparticle-Stabilized Lattices of Topological Defects in Liquid Crystals

We present a review of nanoparticle (NP) stabilized lattices of topological defects (TDs) in liquid crystals (LCs). We focus on conditions for which chiral liquid-crystalline blue phases and twist-grain boundary A phases might be stable in bulk LCs. These phases exhibit lattices of disclinations and dislocations corresponding to line TDs in orientational and translational LC order, respectively. NPs of appropriate size and surface coating can assemble in the cores of defects and stabilize metastable or increase the temperature range of already stable lattices of TDs. The stabilization is achieved by the universal defect core replacement and adaptive defect core targeting mechanisms. Representative experiments revealing these phenomena and potential applications are discussed.