Electrically Driven Multiaxis Rotational Dynamics of Colloidal Platelets in Nematic Liquid Crystals

We describe field-induced multiaxis rotations of colloids in a nematic liquid crystal. Anchoring of the nematic director to the colloidal platelet's surface and interplay of dielectric and elastic energies enable robust control over colloid orientation that cannot be achieved in isotropic liquids. Because of the anisotropy of the fluid and the platelike shape of particles, the colloids can be forced to rotate about four different rotational axes even for a fixed direction of the applied field. The time scale of these unexpected voltage-dependent dynamics varies over four orders of magnitude (10(-2)-10(2) s) and promises a number of novel electro-optic, photonic, and display applications.