Phys Rev E Stat Nonlin Soft Matter Phys
November 2006
Recent works reported planar and conical azimuthally degenerated nematic anchorings. Here we predict an additional "anticonical" degenerated anchoring. Its energy presents two minima, parallel and perpendicular to the substrate plane, separated by a conical energy barrier.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
November 2004
We present experimental evidence of zenithal gliding of the nematic easy axis on a polyimide surface. The reorientation dynamics of the easy axis under external torque, and its relaxation, are extremely slow processes which cannot be described by a single exponential time. They show similarities with aging phenomena previously encountered in glassy systems.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
May 2003
We study the action of a strong electric field on a nematic, topologically stabilized with director n perpendicular to E. Above a threshold field the nematic order on the cell midplane is "melted" and rapidly reconstructed with n axially E. In a Landau-de Gennes model, we show that the observed transient "melted" state is a biaxial nematic and not an isotropic liquid.
View Article and Find Full Text PDFThe relaxation dynamic of a dipole of +1/2 and -1/2 parallel disclination lines in a confined geometry is measured. The confinement and the planar anchoring conditions force the disclinations to be normal to the glass plates. In a first asymptotic regime, the direct elastic interaction between disclination is completely screened out by the anchoring energy.
View Article and Find Full Text PDF