Structure of smectic defect cores: x-ray study of 8CB liquid crystal ultrathin films.
We study the structure of very thin liquid crystal films frustrated by antagonistic anchorings in the smectic phase. In a cylindrical geometry, the structure is dominated by the defects for film thicknesses smaller than 150 nm and the detailed topology of the defects' cores can be revealed by x-ray diffraction. They appear to be split in half tube-shaped rotating grain boundaries (RGB). We determine the RGB spatial extension and evaluate its energy per unit length. Both are significantly larger than the ones usually proposed in the literature.
INSP, Universités Paris 6 et 7, UMR-CNRS 7588, Campus Boucicaut, 140 rue de Lourmel, F-75015 Paris, France.
Jean-Philippe
JP
Michel
Emmanuelle
E
Lacaze
Michel
M
Goldmann
Marc
M
Gailhanou
Marc
M
de Boissieu
Michel
M
Alba