  The application of AC electric fields in aqueous suspensions of anisotropic
particles leads to unbalanced liquid flows and nonlinear, induced-charge
electrophoretic (ICEP) motion. We report experimental observations of the
motion of "Janus" microparticles with one dielectric and one metal-coated
hemisphere induced by uniform fields of frequency 100 Hz - 10 kHz in NaCl
solutions. The motion is perpendicular to the field axis and persists after
particles are attracted to a glass wall. This phenomenon may find applications
in microactuators, microsensors, and microfluidic devices.

Fluid Dynamics