Statics and Dynamics of Colloidal Particles in Liquid Crystals

Oleg D. Lavrentovich
Kent State University
Thursday, September 26, 2013
North Carolina State University EB3 Room 2220 | 4:30pm

The review presents recent progress in studies of statics and electrically induced dynamics of colloidal particles in a nematic liquid crystal (LC).  Elastic repulsion of particles from bounding walls prevents sedimentation and allows supra-micron particles to levitate in the LC bulk.  The electric field causes transport of particles by various mechanisms, including the dielectric torque-triggered backflow, LC-enabled dielectrophoresis [1], and LC-enabled electrophoresis (LCEP) [2]. LCEP is rooted in broken symmetry of the medium and represents a counterpart of the induced-charge electrophoresis (ICEP) in isotropic fluid [3] in which the electrophoretic motion is caused by the broken symmetry of the particle itself.  By controlling the properties of the LC medium (such as director orientation and sign of dielectric anisotropy) and the particle, one can design various 3D trajectories and move the particles from one location to another along a curvilinear path. The work is supported by NSF DMR 1104850.