Orientational Defects near Colloidal Particles in a Nematic Liquid Crystal
J. J. Feng & C. Zhou
J. Colloid Interface Sci. 269, 72-78 (2004).
Abstract - We study the defects near a sphere
strong homeotropic anchoring in a nematic liquid crystal. The
theory is based on a nonlocal nematic potential representing molecular
interactions in an inhomogeneous orientational field. An evolution
for the configuration tensor is solved numerically whose steady state
the total free energy of the system. Three types of solutions may
depending on initial conditions and particle size: Saturn rings,
satellite point defects and polar rings. The Saturn ring remains stable
on micron-sized particles, contrary to previous calculations but
with experiments. A phase diagram is constructed for the three regimes.
Based on the free energy, the most stable state is the Saturn ring for
smaller particles and the satellite defect for larger ones.