  Electrically-controlled dynamics of fluids and particles at microscales is a
fascinating area of research with applications ranging from microfluidics and
sensing to sorting of biomolecules. The driving mechanisms are electric forces
acting on spatially separated charges in an isotropic medium such as water.
Here we demonstrate that anisotropic conductivity of liquid crystals enables
new mechanism of highly efficient electro-osmosis rooted in space charging of
regions with distorted orientation. The electric field acts on these
distortion-separated charges to induce liquid crystal-enabled electro-osmosis
(LCEO). LCEO velocities grow with the square of the field, which allows one to
use an AC field to drive steady flows and to avoid electrode damage. Ionic
currents in liquid crystals that have been traditionally considered as an
undesirable feature in displays, offer a broad platform for versatile
applications such as liquid crystal enabled electrokinetics, micropumping and
mixing.
