title: Rotational solid friction of a nematic liquid crystal.
abstract: Liquid crystal defects are used as probes to study the local reorientation dynamics of the nematic surface director on SiO(x) alignment layers. The tracking of the defect's motion reveals the presence of solid friction forces, unexpected in this complex viscous fluid. We identify the director pinning due to a surface quenched disorder as a possible mechanism that gives rise to the measured solid friction.
authors.affiliation: Laboratoire des Colloïdes, Verres et Nanomatériaux, UMR5587 CNRS and Université Montpellier II, Place Eugène Bataillon, 34095 Montpellier, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Blanc
authors.forename: Mathieu
authors.initials: M
authors.lastname: Nespoulous
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Angot
authors.forename: Maurizio
authors.initials: M
authors.lastname: Nobili