Topological Polymer Dispersed Liquid Crystals with Bulk Nematic Defect Lines Pinned to Handlebody Surfaces

作     者：Michael G. Campbell Mykola Tasinkevych Ivan I. Smalyukh 

作者机构：Department of Physics University of Colorado Boulder Colorado 80309 USA Liquid Crystal Materials Research Center University of Colorado Boulder Colorado 80309 USA Max-Planck-Institut für Intelligente Systeme Heisenbergstraße 3 D-70569 Stuttgart Germany Institut für Theoretische Physik IV Universität Stuttgart Pfaffenwaldring 57 D-70569 Stuttgart Germany Department of Electrical Computer and Energy Engineering and Materials Science and Engineering Program University of Colorado Boulder Colorado 80309 USA Renewable and Sustainable Energy Institute National Renewable Energy Laboratory and University of Colorado Boulder Colorado 80309 USA 

出 版 物：《Physical Review Letters》 (Phys Rev Lett)

年 卷 期：2014年第112卷第19期

页      面：197801-197801页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：National Science Foundation  (DMR-0847782) 

主　　题：NEMATIC liquid crystals RESEARCH POLYMERS -- Research HANDLEBODIES SURFACES (Technology) -- Defects PHYSICS research 

摘      要：Polymer dispersed liquid crystals are a useful model system for studying the relationship between surface topology and defect structures. They are comprised of a polymer matrix with suspended spherical nematic drops and are topologically constrained to host defects of an elementary hedgehog charge per droplet, such as bulk or surface point defects or closed disclination loops. We control the genus of the closed surfaces confining such micrometer-sized nematic drops with tangential boundary conditions for molecular alignment imposed by the polymer matrix, allowing us to avoid defects or, on the contrary, to generate them in a controlled way. We show, both experimentally and through numerical modeling, that topological constraints in nematic microdrops can be satisfied by hosting topologically stable half-integer bulk defect lines anchored to opposite sides of handlebody surfaces. This enriches the interplay of topologies of closed surfaces and fields with nonpolar symmetry, yielding new unexpected configurations that cannot be realized in vector fields, having potential implications for topologically similar defects in cosmology and other fields.