Interparticle potential and drag coefficient in nematic colloids.
Magneto-optic tweezers were used for measurements of liquid-crystal-mediated forces between spherical beads with tangential anchoring in thin nematic samples. Repulsive force, which results from the quadrupolar symmetry of defects around the immersed beads, decreases proportionally to 1/x6, with x being the bead separation. The velocity with which the particles are pushed apart also follows the same separation dependence. We thus find the effective drag coefficient gamma(eff) independent of x for surface-to-surface distances as small as 10% of the bead diameter.
Kotar
Jurij
J
Department of Physics, University of Ljubljana, Jadranska 19, SI-1000 Ljubljana, Slovenia.
Vilfan
Mojca
M
Osterman
Natan
N
Babic
Dusan
D
Copic
Martin
M
Poberaj
Igor
I