Dynamics of Nematic Liquid Crystal Disclinations: The Role of the Backflow Auteur(s): Blanc C., Svenšek D., Žumer S., Nobili M. (Article) Publié: Physical Review Letters, vol. 95 p.097802 (2005) Ref HAL: hal-01207474_v1 PMID 16197250 DOI: 10.1103/PhysRevLett.95.097802 WoS: 000231503600062 Exporter : BibTex | endNote 74 Citations Résumé: We measure the electric-field-driven annihilation of nematic disclination pairs with strength ±1/2 in the 4−cyano−4′−n-pentylbiphenyl (5CB) liquid crystal. The use of a very weak azimuthal anchoring ensures a two-dimensional director field. The relaxation is governed by the formation of a π wall connecting the two opposite charge defects. The +1/2 disclinations move almost twice as fast as the −1/2 disclinations. The simple used geometry allows a quantitative comparison with numerical studies based on the hydrodynamics of the tensorial order parameter. The simulations show that in the π wall regime the symmetry breaking is due to the backflow and not to the elastic anisotropy. |